The 21st Century: Digital Revolution, Climate Crisis, and Shifting Power

Note on currency. This unit describes events that are still unfolding. Factual claims are dated to the best available evidence as of early 2026. Sections on COVID-19, democratic backsliding, the Russia-Ukraine war, artificial intelligence, and the energy transition will need regular revision. The structure and analytical frameworks should remain stable even as specifics change.

Overview Beginner

The 21st century began with a promise and a shock. The promise was globalisation: the end of the Cold War had supposedly ended history, and liberal democracy and free markets would spread across the world. The shock came on September 11, 2001, when 19 men hijacked four aeroplanes, crashed two into the World Trade Center in New York and one into the Pentagon, and killed nearly 3,000 people. A fourth plane, United 93, was brought down by its passengers in a field in Pennsylvania. The world that emerged after 9/11 was not the one anyone had predicted.

This unit covers the major forces shaping the 21st century: the digital revolution, climate change, shifting power structures, the War on Terror, social movements, refugee crises, a pandemic, and the rise and retreat of democracy. Each topic is presented from multiple perspectives. There is no single story of the 21st century because the century is being experienced differently by different people in different places.

The digital revolution: connectivity and surveillance Beginner

In 2000, roughly 400 million people used the internet. By 2025, that number exceeded 5 billion. Mobile phones went from luxury items to ubiquitous tools. Social media platforms, beginning with Friendster and MySpace and then dominated by Facebook (launched 2004), Twitter (2006), and later Instagram (2010), TikTok (2016), and others, created new ways for people to connect, organise, argue, and spread information and disinformation.

The smartphone revolutionised daily life. Apple's iPhone, launched in 2007, put a powerful computer, camera, GPS, and internet connection in a pocket-sized device. Within a decade, smartphones had transformed how people communicate, navigate, shop, date, read news, and spend their time. In many parts of the Global South, people leapfrogged landlines and desktop computers entirely, accessing the internet primarily through mobile devices.

But the digital revolution had a dark side. The business model of the major platforms depended on capturing user attention and selling it to advertisers. Every click, like, search, and location was tracked, recorded, and analysed. Shoshana Zuboff called this "surveillance capitalism": the transformation of human experience into data that could be harvested, predicted, and sold. The user was not the customer. The user was the product.

Governments also used digital tools for surveillance. In 2013, former US National Security Agency contractor Edward Snowden leaked classified documents revealing that the NSA was collecting telephone records and internet data on millions of people, including American citizens, without warrants. The revelations sparked a global debate about the balance between security and privacy. From the perspective of intelligence agencies, mass surveillance was necessary to prevent terrorism. From the perspective of civil liberties advocates, it was a fundamental violation of the right to privacy.

China built the most sophisticated surveillance state in history. The "Great Firewall" blocked access to foreign websites. A social credit system tracked citizens' behaviour and restricted access to services for those deemed untrustworthy. Facial recognition cameras monitored public spaces. The Chinese government framed these measures as tools for public safety and social harmony. Critics described them as instruments of authoritarian control.

Social media: connection, division, and the attention economy Beginner

Social media connected people across the globe. It enabled political organising, from the Arab Spring to Black Lives Matter. It gave voice to people who had been excluded from traditional media. It allowed communities to form around shared interests regardless of geography.

It also enabled the rapid spread of false information. Conspiracy theories, fabricated news stories, and deliberate disinformation campaigns reached millions of people within hours. During the 2016 American presidential election, Russian operatives used social media to spread divisive content and suppress voter turnout among specific demographics. Facebook's own internal research, leaked by whistleblower Frances Haugen in 2021, showed that the company knew its algorithms amplified anger and division because angry content generated more engagement and more profit.

The impact on mental health, particularly among young people, became a growing concern. Rates of anxiety, depression, and self-harm among adolescents rose sharply in many countries during the 2010s, correlating with the widespread adoption of smartphones and social media. The relationship was debated: some researchers argued that correlation was not causation, while others pointed to the specific mechanisms by which social comparison, cyberbullying, and algorithmic feed design contributed to psychological distress.

Climate change: the crisis of the century Beginner

The scientific consensus on climate change is overwhelming. The Intergovernmental Panel on Climate Change (IPCC), which brings together thousands of the world's leading climate scientists, stated in its Sixth Assessment Report (2021-2023) that human activities, primarily the burning of fossil fuels, have warmed the planet by approximately 1.1 degrees Celsius above pre-industrial levels. This warming is causing rising sea levels, more intense storms, prolonged droughts, devastating wildfires, melting ice caps, and the acidification of oceans.

The 2015 Paris Agreement committed 196 countries to limit global warming to well below 2 degrees Celsius, and preferably to 1.5 degrees. Each country submitted its own emissions reduction targets. The agreement was hailed as a landmark achievement. But the targets submitted were insufficient to meet the goals they were supposed to achieve, and many countries, including some of the largest emitters, were not on track to meet even their own inadequate targets.

Climate change is not experienced equally. The countries that contributed least to the problem are suffering the most. This is the central injustice of the climate crisis.

Climate change: responsibility, emissions, and vulnerability Beginner

The question of who is responsible for climate change has three dimensions, and each tells a different story.

The historical dimension looks at cumulative emissions since the Industrial Revolution. On this measure, the United States and Europe bear the greatest responsibility. The United States alone has produced roughly 20 percent of all historical carbon dioxide emissions. The European Union has produced roughly 17 percent. Together, they account for more than a third of all the greenhouse gases humans have ever put into the atmosphere. These emissions fuelled the industrialisation that made the West wealthy.

The current emissions dimension looks at who is emitting the most right now. China is now the world's largest emitter of greenhouse gases, producing roughly 30 percent of the global total. But China's per capita emissions remain lower than those of the United States, and much of China's emissions come from manufacturing goods that are consumed in the West. India's emissions are growing rapidly but its per capita emissions remain well below the global average.

The vulnerability dimension looks at who suffers the most. Pacific Island nations like Tuvalu, Kiribati, and the Marshall Islands face existential threat from rising sea levels. Some could become uninhabitable within decades. Bangladesh, a country of 170 million people, is highly vulnerable to flooding, cyclones, and sea-level rise. Sub-Saharan Africa, which has contributed less than 4 percent of historical global emissions, is experiencing some of the most severe droughts, floods, and agricultural disruptions.

From the perspective of the Global South, the wealthy industrialised nations grew rich by burning fossil fuels and now demand that developing nations forgo the same path. From the perspective of the industrialised nations, every country must reduce emissions regardless of historical responsibility because the climate does not care about fairness. Both perspectives have merit. The tension between them has defined international climate negotiations for decades.

9/11 and the War on Terror: the American perspective Beginner

The September 11 attacks traumatised the United States. Nearly 3,000 people were killed in a single morning. The images of the twin towers collapsing were seared into the national consciousness. For Americans, 9/11 was an act of unimaginable violence perpetrated on innocent civilians by a foreign enemy. The country felt vulnerable in a way it had not felt since Pearl Harbor.

The American response was swift. President George W. Bush declared a "War on Terror." In October 2001, the United States invaded Afghanistan, where the Taliban government had provided safe haven to al-Qaeda, the organisation responsible for the attacks. The invasion had broad international support. NATO invoked Article 5, its mutual defence clause, for the first and only time in its history. Dozens of countries joined the coalition.

The initial military campaign was successful by its own narrow terms. The Taliban were driven from power within weeks. Al-Qaeda's leadership, including Osama bin Laden, fled into the mountains along the Pakistan border. But the United States then committed to nation-building: creating a democratic, stable Afghanistan that would never again harbour terrorists. This proved far more difficult than anticipated.

In March 2003, the United States invaded Iraq, claiming that Saddam Hussein's regime possessed weapons of mass destruction and had ties to al-Qaeda. Both claims were false. The Iraq War would prove to be one of the most consequential and controversial military interventions of the 21st century.

The War on Terror: Afghan and Iraqi perspectives Beginner

From the American perspective, the War on Terror was a response to an unprovoked attack. From the perspective of the people who lived in Afghanistan and Iraq, it was something very different.

In Afghanistan, the US-led invasion displaced the Taliban but did not bring peace. The war lasted twenty years, making it the longest war in American history. During that time, roughly 176,000 Afghans were killed, including at least 46,000 civilians. Millions more were displaced. The American-backed Afghan government was corrupt and unable to provide security or services outside major cities. The Taliban regrouped, funded by opium production and support from elements within Pakistan.

When American and coalition forces withdrew in August 2021, the Afghan government collapsed within days. The Taliban returned to power. Twenty years of war, trillions of dollars spent, and tens of thousands of lives lost ended with the same group in control that had been there before the invasion. From the Afghan perspective, the war brought suffering, instability, and then a return to the starting point.

Iraq suffered even more. The 2003 invasion was based on false claims about weapons of mass destruction. The Chilcot Report, the British government's official inquiry into the Iraq War published in 2016, concluded that the war was not a last resort, that the threat from Iraq was not imminent, and that the planning for post-invasion Iraq was "wholly inadequate."

The invasion and its aftermath killed hundreds of thousands of Iraqis. A 2013 study by researchers from the University of Washington and MIT estimated roughly 460,000 excess deaths in Iraq from 2003 to 2011. The war destroyed infrastructure, dismantled state institutions, and created a power vacuum that fuelled sectarian violence. The militant group ISIS, which emerged from the chaos of post-invasion Iraq, would later conquer vast territory and commit atrocities that shocked the world.

From the Iraqi perspective, the war was not a liberation. It was a catastrophic intervention that destroyed a country and killed a staggering number of its people based on claims that turned out to be false.

The rise of China: development and authoritarianism Beginner

China's economic rise is one of the defining stories of the 21st century. In 2000, China's economy was roughly one-tenth the size of the American economy. By 2025, it was the second largest in the world by nominal GDP and the largest by purchasing power parity. Hundreds of millions of Chinese citizens were lifted out of poverty. China became the world's manufacturing centre, producing goods consumed globally.

From the perspective of the Chinese government and many Chinese citizens, this rise represents a legitimate national development. After a century of humiliation by foreign powers, including the Opium Wars, Japanese invasion, and periods of famine and chaos, China has reclaimed its position as a major power. The Belt and Road Initiative, launched in 2013, invested hundreds of billions of dollars in infrastructure projects across Asia, Africa, and Europe, extending Chinese economic influence globally.

From the perspective of China's critics, the rise has been accompanied by increasing authoritarianism. The Chinese Communist Party has tightened control over information, expanded surveillance, suppressed dissent, and imprisoned human rights lawyers and journalists. The treatment of the Uyghur Muslim minority in Xinjiang, which multiple governments and human rights organisations have described as crimes against humanity and some have called genocide, included the detention of over a million people in camps, forced labour, and cultural suppression. The Chinese government has denied these charges.

China's rise presents the 21st century with a fundamental tension: can a country achieve extraordinary economic development while maintaining authoritarian political control? The Chinese government argues that its system is effective and that Western-style democracy is not the only legitimate model. Critics argue that economic development without political freedom is incomplete and unstable.

A multipolar world: BRICS and shifting power Beginner

The end of the Cold War left the United States as the world's sole superpower. The 1990s and early 2000s were sometimes called the "unipolar moment." By the 2020s, that moment was ending.

The BRICS grouping, originally Brazil, Russia, India, China, and South Africa, and later expanded to include Egypt, Ethiopia, Iran, Saudi Arabia, and the United Arab Emirates, represented a shift in global power away from Western dominance. BRICS nations together accounted for roughly 45 percent of the world's population and a growing share of global GDP. They established the New Development Bank as an alternative to the Western-dominated World Bank and IMF.

The shift toward multipolarity was not simply about economics. It reflected a growing reluctance among many countries to accept American or Western leadership as automatic. The Iraq War, which much of the world viewed as an illegal invasion, damaged American credibility. The 2008 financial crisis, which originated in the American housing market and spread globally, undermined confidence in Western economic management. The COVID-19 pandemic exposed the limitations of every major power's response capabilities.

From the perspective of the West, the shift toward multipolarity threatened the rules-based international order that had maintained relative peace since 1945. From the perspective of many nations in the Global South, that order had never been as rules-based or as beneficial as the West claimed. The same institutions that preached free trade protected Western agricultural subsidies. The same countries that championed human rights sold arms to authoritarian regimes.

Russia's invasion of Ukraine in February 2022 dramatically intensified the question of global order. The largest land war in Europe since 1945 killed hundreds of thousands, displaced millions, and reshaped energy markets and alliances. Western countries imposed sweeping sanctions on Russia and provided military and financial support to Ukraine. Many countries in the Global South chose not to align with either side, reflecting both pragmatic economic interests and a reluctance to be drawn into what they saw as a European conflict.

The Arab Spring: hope and aftermath Beginner

In December 2010, a street vendor named Mohamed Bouazizi set himself on fire in the Tunisian town of Sidi Bouzid after police confiscated his cart and humiliated him. His act of desperation sparked protests that spread across Tunisia. Within weeks, the Tunisian dictator Zine El Abidine Ben Ali fled the country. The protests spread to Egypt, Libya, Yemen, Bahrain, and Syria. This wave of uprisings became known as the Arab Spring.

The Arab Spring was driven by a generation of young people across the Middle East and North Africa who were educated, connected through social media, and frustrated by authoritarian rule, corruption, unemployment, and lack of opportunity. They wanted dignity, democracy, and economic justice. In the early months of 2011, it felt as though a political transformation was sweeping the region.

The outcomes diverged sharply.

Tunisia is often described as the partial success of the Arab Spring. It adopted a new constitution in 2014 that was among the most progressive in the Arab world, guaranteeing freedom of religion and gender equality. But economic problems persisted, and by 2021, democratic institutions were under strain as the president suspended parliament and consolidated power.

Egypt experienced a brief democratic opening. Long-time president Hosni Mubarak resigned in February 2011. Free elections in 2012 brought Mohamed Morsi of the Muslim Brotherhood to power. But Morsi's government was ineffective and polarising. In July 2013, the military, led by General Abdel Fattah el-Sisi, removed Morsi in a coup. Sisi became president and governed more autocratically than Mubarak had. The Arab Spring in Egypt ended with a return to military rule.

Libya collapsed into civil war. NATO intervened militarily to protect civilians from Muammar Gaddafi's forces, and Gaddafi was captured and killed in October 2011. But no functioning government emerged to replace him. Libya descended into factional fighting between militias, became a route for migrants attempting to reach Europe, and remained fragmented for years.

Syria experienced the worst outcome. Peaceful protests in March 2011 were met with violent repression by the government of Bashar al-Assad. The conflict escalated into a full-scale civil war that drew in regional and international powers. Russia and Iran supported Assad. The United States, Turkey, and various Gulf states supported different rebel factions. ISIS seized territory in eastern Syria and western Iraq. By 2025, the war had killed roughly 500,000 people and displaced roughly 13 million, roughly half the country's pre-war population. Large parts of Syrian cities lay in ruins.

From the perspective of those who participated in the Arab Spring, the uprisings were a courageous demand for dignity and self-determination. The hope they felt in early 2011 was genuine. The aftermath, in most cases, was devastating. But the desire for freedom and justice that drove the Arab Spring has not disappeared. It persists, waiting.

Refugee crises: displacement in the 21st century Beginner

The 21st century has produced the largest number of displaced people since World War II. By 2024, the United Nations High Commissioner for Refugees estimated that over 117 million people had been forcibly displaced from their homes. This included refugees who had crossed international borders, internally displaced people who had fled within their own countries, and asylum seekers awaiting determination of their status.

The Syrian refugee crisis was the largest since the war. Roughly 6.8 million Syrians fled the country, with the largest numbers hosted by Turkey, Lebanon, Jordan, and Germany. Lebanon, a country of roughly 6 million people, took in roughly 1.5 million Syrian refugees, placing enormous strain on its economy and social services. The arrival of large numbers of refugees in Europe in 2015 sparked a political crisis that fuelled the rise of far-right parties across the continent.

The Rohingya crisis displaced roughly 740,000 members of the Rohingya Muslim minority from Myanmar (Burma) in 2017. Myanmar's military conducted what the United Nations described as a textbook example of ethnic cleansing, burning villages, killing civilians, and driving the Rohingya into neighbouring Bangladesh. The Rohingya, whom Myanmar refused to recognise as citizens, had faced decades of discrimination. Nearly a million Rohingya lived in crowded refugee camps in Bangladesh, with no prospect of safe return.

Central American migration to the United States was driven by a combination of violence, poverty, and political instability in Guatemala, Honduras, and El Salvador. These countries, sometimes called the Northern Triangle, had some of the highest homicide rates in the world. Gang violence, weak institutions, and the legacy of civil wars and American interventions in the 1980s created conditions that made daily life dangerous for millions. Families and unaccompanied children undertook dangerous journeys north, facing exploitation, violence, and the possibility of detention and deportation.

From the perspective of refugees, displacement is a catastrophe imposed on them by forces beyond their control. From the perspective of host countries, the arrival of large numbers of refugees creates genuine pressures on housing, employment, public services, and social cohesion. Both perspectives are real. The political challenge is responding to both honestly.

COVID-19: a pandemic in a connected world Beginner

In late 2019, a novel coronavirus emerged in Wuhan, China. The virus, designated SARS-CoV-2, caused the disease COVID-19. It spread rapidly around the world. The World Health Organization declared a pandemic on March 11, 2020. By early 2026, the pandemic had killed over 7 million people confirmed, with estimates of excess mortality ranging from 15 to 25 million.

The pandemic exposed and intensified existing inequalities. In many countries, wealthy professionals worked from home while essential workers, often low-paid and from minority communities, faced greater exposure to the virus. The shift to remote work was feasible for some and impossible for others, widening the gap between those who could shelter safely and those who could not.

Different countries experienced the pandemic very differently. China imposed strict lockdowns, containing the virus initially but at enormous social cost. New Zealand and Taiwan pursued elimination strategies that kept cases near zero for extended periods. The United States, which had the most reported cases and deaths of any country, experienced a fragmented response shaped by political polarisation. Public health measures including mask-wearing and vaccination became partisan identity markers. India experienced a devastating second wave in spring 2021 that overwhelmed hospitals and crematoriums; oxygen ran out; people died in parking lots. Africa had lower reported mortality than many expected, though testing was limited and the true toll remains debated.

Vaccine development was historically rapid. Multiple effective vaccines were developed, tested, and authorised within a year, a process that previously took a decade or more. But vaccine distribution was deeply unequal. Wealthy countries secured doses far in excess of their populations while many poorer countries waited. The COVAX initiative, designed to ensure equitable distribution, was underfunded and slow. By the time vaccines became widely available in sub-Saharan Africa, wealthy nations were already administering boosters.

The pandemic's economic consequences were vast. Global GDP contracted by roughly 3.1 percent in 2020, the deepest recession since the Second World War. Supply chains were disrupted. Government debt rose sharply. The shift toward digital work, already underway, accelerated dramatically. The pandemic changed how millions of people worked, learned, socialised, and thought about risk.

Black Lives Matter and global movements for justice Beginner

On May 25, 2020, a white police officer in Minneapolis, Minnesota, murdered George Floyd, a Black man, by kneeling on his neck for over nine minutes. A bystander's video of the killing was viewed millions of times. Protests erupted across the United States and spread to dozens of countries, becoming what was likely the largest protest movement in American history.

Black Lives Matter, founded in 2013 after the acquittal of the man who killed Trayvon Martin, became the organisational framework for demands to address police violence, systemic racism, and the legacy of slavery and discrimination in the United States. The movement demanded not only an end to police brutality but a reckoning with the ways that racism shaped housing, education, healthcare, employment, and the criminal justice system.

The movement resonated globally. In the United Kingdom, protesters toppled a statue of slave trader Edward Colston in Bristol and demanded recognition of the British Empire's role in the slave trade. In France, the death of Adama Traore in police custody in 2016 returned to public attention. In Brazil, where police violence disproportionately killed Black and mixed-race Brazilians, activists drew connections to the American movement. In Australia, the movement highlighted the disproportionate incarceration and deaths of Aboriginal people in custody.

From the perspective of activists, these movements were long-overdue demands for justice that had been denied for generations. From the perspective of critics, they went too far, polarising societies and undermining social cohesion. The tension between these perspectives shaped politics across multiple continents during the 2020s.

#MeToo: a global reckoning with sexual violence Beginner

In October 2017, the New York Times and the New Yorker published investigations documenting decades of sexual harassment and assault by film producer Harvey Weinstein. The reports prompted millions of women around the world to share their own experiences of sexual harassment and assault on social media using the hashtag #MeToo, a phrase originally coined by activist Tarana Burke in 2006.

The movement exposed the prevalence of sexual violence and harassment across every industry and society. Powerful men in entertainment, media, politics, business, and sports were held accountable for behaviour that had previously been tolerated or concealed. The movement led to new laws, workplace policies, and a shift in social norms about what was acceptable.

The movement also sparked debate. Some argued that it had gone too far, that due process was being bypassed, and that the resulting climate of fear harmed relationships between men and women. Others argued that it had not gone far enough, that powerful men continued to evade accountability, and that the movement had disproportionately benefited white, wealthy women while women of colour, domestic workers, and women in the Global South saw little change in their daily experiences of harassment and violence.

Democratic backsliding: the retreat of freedom Beginner

The early 21st century saw a troubling trend: the decline of democratic governance in countries that had previously been considered democracies. This was not a return to the overt dictatorships of the 20th century. It was something more subtle: the erosion of democratic institutions from within.

In Hungary, Prime Minister Viktor Orban, re-elected repeatedly from 2010 onward, rewrote the constitution, packed the courts, took control of the media, and cracked down on civil society organisations, particularly those funded by the Hungarian-American philanthropist George Soros. Orban openly described his model as "illiberal democracy," arguing that Hungary was a democracy that did not need to follow liberal Western norms.

In Turkey, President Recep Tayyip Erdogan used a failed military coup in July 2016 as justification for a sweeping crackdown. Over 100,000 people were arrested or dismissed from their jobs. Newspapers were shut down. Judges were replaced. Erdogan consolidated presidential power through a constitutional referendum that eliminated the office of prime minister.

In the Philippines, President Rodrigo Duterte, elected in 2016, launched a "war on drugs" that killed an estimated 12,000 to 30,000 people, most of them poor, without trial. Death squads operated with impunity. Duterte dismissed human rights concerns and boasted about the killings.

In Brazil, President Jair Bolsonaro, elected in 2018, attacked the press, praised the country's military dictatorship, weakened environmental protections in the Amazon, and, after losing re-election in 2022, refused to concede, with his supporters storming government buildings in January 2023 in an echo of the January 6, 2021 attack on the US Capitol by supporters of Donald Trump.

From the perspective of these leaders and their supporters, they were democratically elected leaders carrying out the will of the people against entrenched elites. From the perspective of democracy monitors and civil society organisations, they were autocrats using democratic procedures to undermine democracy itself.

The future of work: automation, AI, and the Anthropocene Beginner

The 21st century is reshaping work. Automation and artificial intelligence are transforming industries from manufacturing to law to medicine. Tasks that once required human judgment are being performed by machines. Self-driving vehicles threaten millions of jobs in trucking and delivery. AI systems can write code, generate text, analyse legal documents, and create art.

The benefits of automation are substantial: higher productivity, lower costs, and the elimination of dangerous and tedious work. The costs are also substantial: displacement of workers whose skills are rendered obsolete, growing inequality between those who own and control the technology and those who do not, and the psychological toll of economic insecurity.

The concept of the Anthropocene captures the idea that human activity has become the dominant force shaping the Earth's geology and ecosystems. The term, proposed by atmospheric chemist Paul Crutzen in 2000, reflects the reality that humans have altered the climate, acidified the oceans, deforested vast areas, polluted waterways, driven species to extinction at rates not seen since the asteroid impact that killed the dinosaurs, and deposited layers of plastic and radioactive material that will be detectable in the geological record for millions of years.

The Anthropocene forces a question that previous generations did not face: can humanity manage its own power? The technologies of the 21st century give humans god-like capabilities. The wisdom to use them responsibly has not kept pace.

Worked example: comparing national COVID-19 responses Beginner

Consider how three countries responded to COVID-19 in early 2020 and what happened.

New Zealand (population 5 million) pursued an elimination strategy. The government closed borders early, imposed a strict nationwide lockdown, and implemented comprehensive testing and contact tracing. By June 2020, the country had essentially eliminated community transmission. Life returned to near-normal for extended periods. The trade-off was strict border controls that kept citizens abroad separated from families. By late 2021, when the more transmissible Delta variant arrived, elimination became impossible and the country transitioned to living with the virus.

The United States (population 330 million) had a fragmented response. The federal government under President Trump initially downplayed the virus, then adopted a strategy of leaving major decisions to state governments. This produced a patchwork: some states imposed strict lockdowns, others resisted. Mask mandates became politically polarised. Vaccine uptake varied dramatically by region and political affiliation. The result was the highest confirmed death toll of any country, over 1 million by early 2025.

India (population 1.4 billion) imposed one of the strictest lockdowns in the world in March 2020 with just four hours' notice. The sudden lockdown stranded millions of migrant workers in cities without work, food, or transport, forcing them to walk hundreds of kilometres to their home villages. The initial lockdown slowed the virus but caused enormous economic hardship. When restrictions eased, cases surged. The second wave in April-May 2021 was catastrophic: hospitals ran out of oxygen, crematoriums operated around the clock, and the official death toll, already a significant undercount, spiked.

What this tells us: the same virus produced very different outcomes depending on government capacity, social trust, political leadership, population size, and the trade-offs each society was willing to accept between public health and economic activity. No country got everything right. Some got much more wrong than others.

Check your understanding Beginner

Formal definition: key analytical frameworks Intermediate+

The 21st century requires a set of analytical frameworks that did not exist or were not central to earlier periods. These frameworks define the terms of debate and the categories through which events are interpreted. They are defined here because each captures a structural feature of the contemporary world that recurs across the topics covered in this unit.

Surveillance capitalism

Zuboff defines surveillance capitalism as a new economic logic that claims human experience as raw material for translation into behavioural data. This data is then processed by machine intelligence and fabricated into "prediction products" that anticipate what people will do now, soon, and later. These products are sold in "behavioural futures markets." The key innovation is that the data is not used to improve services for users but to predict and influence user behaviour for the benefit of advertisers and other commercial and political actors.

The mechanism operates through three stages: extraction (capturing data from user activity), analysis (processing data through machine learning to identify patterns), and targeting (using those patterns to influence future behaviour). The result is an asymmetric relationship in which the platforms know vastly more about users than users know about the platforms.

Historical responsibility and common but differentiated responsibilities

The United Nations Framework Convention on Climate Change (1992) established the principle of "common but differentiated responsibilities and respective capabilities." This principle acknowledges that all nations have an obligation to address climate change but that this obligation is not equal. Nations that industrialised early and emitted more greenhouse gases over a longer period bear a greater responsibility for the accumulated concentration of atmospheric carbon dioxide.

The principle is contested. The United States and other developed nations have often resisted the implication that they owe financial transfers to developing nations for climate adaptation and mitigation. Developing nations argue that the principle requires concrete action, not merely acknowledgment. The Paris Agreement (2015) attempted to bridge this gap through nationally determined contributions, but the voluntary nature of these commitments means the principle operates more as a normative framework than as an enforceable obligation.

Democratic backsliding

Political scientists Steven Levitsky and Daniel Ziblatt, in their 2018 work How Democracies Die, identified a pattern in which elected leaders gradually undermine democratic institutions without formally abolishing them. The playbook includes: capturing the courts, neutralising the media, politicising the civil service and security services, delegitimising opposition, and changing electoral rules to entrench power. The process is gradual enough that each individual step can be defended as legal and legitimate, but the cumulative effect is the transformation of a democracy into an autocracy.

This pattern differs from the 20th-century model of military coups and revolutions. The new autocrats are elected. They use democratic procedures to weaken democracy. They maintain the forms, elections, parliaments, and courts, while draining them of substantive power.

The Anthropocene as analytical framework

The Anthropocene, formally proposed as a geological epoch by the Working Group on the Anthropocene in 2016, identifies the mid-20th century as the point at which human activity became the primary driver of planetary change. The proposed starting point, the "Great Acceleration" of the 1950s, coincides with the rapid expansion of industrial production, fossil fuel consumption, population growth, and the global spread of synthetic materials including plastics and radioactive isotopes from nuclear weapons testing.

The concept is analytically useful because it reframes environmental problems not as external disruptions to an otherwise stable system but as the predictable consequences of a specific economic and technological trajectory. Climate change, biodiversity loss, ocean acidification, and pollution are not separate crises. They are symptoms of a single systemic condition: the scale of human activity has exceeded the capacity of planetary systems to absorb its effects.

Comparative framework: the War on Terror from three perspectives Intermediate+

The American perspective

The United States entered the War on Terror from a position of genuine shock and moral conviction. 9/11 was the deadliest foreign attack on American soil in history. The American public overwhelmingly supported military action. The strategic logic was straightforward: deny terrorists safe haven, disrupt their networks, and deter state sponsorship of terrorism.

The American perspective emphasised the moral clarity of the response. Al-Qaeda had attacked civilians without provocation. The Taliban had sheltered them. Saddam Hussein was a brutal dictator who had used chemical weapons against his own people and invaded a neighbouring country. From within this framework, military intervention was not merely justified but obligatory.

The costs to the United States were substantial: roughly 7,000 military deaths in Afghanistan and Iraq, over 50,000 wounded, trillions of dollars in expenditure, and a deep strain on public trust in government institutions after the false WMD claims and the revelations of torture at Abu Ghraib and elsewhere.

The Afghan perspective

The Afghan experience of the War on Terror was defined by two decades of violence, instability, and foreign military presence. While many Afghans initially welcomed the removal of the Taliban, the subsequent occupation brought drone strikes that killed civilians, night raids on homes, a corrupt and ineffective government propped up by foreign money, and a resurgent insurgency that made large parts of the country ungovernable.

The Afghan perspective notes that the United States supported the mujahideen against the Soviet Union in the 1980s, contributing to the conditions that produced the Taliban in the 1990s, and then invaded in 2001 to remove the group that its own earlier policies had helped create. The circularity of the intervention is difficult to miss.

The Iraqi perspective

The Iraqi experience of the War on Terror began with an invasion that the majority of Iraqis did not request and that was justified by claims that proved false. The dissolution of the Iraqi army and the de-Baathification programme, which purged members of Saddam Hussein's party from government positions, threw hundreds of thousands of armed, trained men into unemployment and humiliation. This policy, more than any other single decision, fuelled the insurgency.

The sectarian violence that followed the invasion killed civilians at rates that dwarfed the violence under Saddam Hussein. Car bombs, death squads, and ethnic cleansing transformed mixed neighbourhoods into sectarian enclaves. The emergence of ISIS in 2014 was a direct consequence of the power vacuum and the alienation of Iraq's Sunni minority.

The Iraqi perspective does not idealise the pre-2003 period. Saddam Hussein was a brutal dictator. But the intervention made things worse by almost every measure available to the people who lived there: deaths, displacement, infrastructure destruction, institutional collapse, and the loss of a generation's opportunity for stable development.

Case study: climate justice and the Pacific Islands Intermediate+

The Pacific Island nations provide the starkest illustration of climate injustice. Kiribati, a nation of roughly 120,000 people spread across 33 atolls, has a maximum elevation of roughly 3 metres above sea level. As sea levels rise, saltwater intrudes into freshwater supplies, king tides flood homes and farmland, and the long-term habitability of the entire nation is in question.

Former Kiribati president Anote Tong purchased land in Fiji as a potential refuge for his people. The government considered building floating platforms. These are not abstract policy proposals. They are contingency plans for the possible dissolution of a nation.

Tuvalu, with roughly 11,000 people, faces similar existential threat. In 2021, Tuvalu's foreign minister, Simon Kofe, addressed the UN climate conference while standing knee-deep in seawater. The image was designed to make the abstract concrete: for Tuvalu, climate change was not a future risk but a present reality.

The combined historical carbon emissions of all Pacific Island nations are negligible, less than 0.01 percent of the global total. Their contribution to the problem is essentially zero. Their exposure to its consequences is nearly total.

The case illustrates the three dimensions of climate justice identified in the Beginner section. Historical responsibility: the Pacific Islands did not cause the problem. Current emissions: they are not contributing to it. Vulnerability: they are among those most threatened by it. The frameworks of international law and climate diplomacy were not designed to handle this degree of asymmetry between cause and effect.

Institutional analysis: BRICS and the post-Western order Intermediate+

The original BRIC acronym was coined by Goldman Sachs economist Jim O'Neill in 2001 to describe the large emerging economies expected to dominate the global economy by mid-century. The four nations, Brazil, Russia, India, and China, began holding formal summits in 2009. South Africa joined in 2010, making it BRICS.

The grouping's significance is both economic and symbolic. Economically, the BRICS nations represented a growing share of global GDP, trade, and energy consumption. Symbolically, they represented a challenge to the Western-dominated institutions of global governance: the World Bank, the International Monetary Fund, and the G7.

The New Development Bank, established by BRICS in 2014 with initial capital of $100 billion, provided development financing without the structural adjustment conditions that the IMF and World Bank typically imposed. The Contingent Reserve Arrangement provided a mutual safety net for balance-of-payments crises. These institutions were not replacements for the Western-dominated system but alternatives that gave member countries options they had not previously had.

The expansion of BRICS in 2024 to include several Middle Eastern nations complicated the grouping's coherence. The original members had divergent political systems (democracies, autocracies, and everything in between), divergent economic interests (energy exporters and importers, manufacturing powerhouses and commodity producers), and divergent strategic orientations. What united them was a shared desire for greater influence in global governance and a shared perception that the existing system was stacked against them.

Exercises Intermediate+

Competing perspectives Master

The War on Terror: security, trauma, and imperial hubris

The War on Terror can be analysed through at least four analytical lenses that produce different evaluations of the same events.

Through the lens of security studies, the American response to 9/11 was a rational attempt to deny terrorist organisations the territorial safe havens from which they planned attacks. The disruption of al-Qaeda's leadership, the destruction of its training camps, and the prevention of subsequent large-scale attacks on American soil are cited as evidence that the strategy succeeded in its primary objective.

Through the lens of international law, the Iraq War was an illegal act of aggression. The UN Charter prohibits the use of force except in self-defence or with Security Council authorisation. The US-led invasion had neither. The Chilcot Report's conclusion that Iraq posed no imminent threat and that military action was not a last resort supports this reading.

Through the lens of postcolonial analysis, the War on Terror reproduced patterns of Western military intervention in the Global South that had characterised the colonial and Cold War eras. The decisions about which countries to invade, which dictators to support, and which lives counted were shaped by the same hierarchies of power and value that had governed earlier interventions. The hundreds of thousands of Arab and Muslim civilian deaths generated a fraction of the moral and political attention that 3,000 American deaths generated.

Through the lens of the people who lived through it, the War on Terror was a period of violence, fear, and disruption that lasted far longer and cost far more than anyone predicted. The Afghan farmer whose fields were destroyed by combat, the Iraqi mother whose child was killed by a car bomb, the Yemeni wedding party killed by a drone strike: these experiences do not fit neatly into any analytical framework.

Climate change: three frameworks in tension

The historical responsibility framework holds that the nations that industrialised first, primarily in Western Europe and North America, bear the greatest obligation to address climate change because they created the problem. On this view, the roughly 1.1 degrees of warming already locked in is primarily the result of emissions from nations that grew wealthy by burning fossil fuels. Justice requires that these nations lead in emissions reductions and provide financial support to nations facing the worst effects.

The current emissions framework emphasises that effective climate action requires participation from all major emitters, including China and India. The atmosphere does not distinguish between historical and current emissions. A ton of carbon dioxide emitted today has the same warming effect regardless of the emitting nation's history. On this view, any solution must include commitments from the largest current emitters, regardless of historical responsibility.

The vulnerability framework shifts the focus from who caused the problem to who faces the gravest consequences. Pacific Island nations, Bangladesh, sub-Saharan African nations, and low-lying coastal regions across the Global South face threats ranging from existential (complete loss of territory) to catastrophic (mass displacement, agricultural collapse, extreme weather). On this view, climate policy should be organised around the needs of the most vulnerable rather than the interests of the most powerful.

No single framework is adequate. The historical framework ignores current reality. The current framework ignores equity. The vulnerability framework ignores the political necessity of securing participation from major emitters. The productive tension between them has driven three decades of climate diplomacy and will continue to do so.

China's rise: legitimate development and authoritarian challenge

The analysis of China's rise depends fundamentally on which dimension is placed at the centre of evaluation.

Evaluated as a development story, China's trajectory since 1978 is one of the most remarkable in human history. Economic reforms initiated by Deng Xiaoping lifted roughly 800 million people out of poverty. China transformed from an impoverished agrarian society into the world's second-largest economy, its largest manufacturer, and a leader in renewable energy technology. The Chinese government and many Chinese citizens argue that this achievement demonstrates the effectiveness of the Chinese model and that Western criticism reflects an inability to accept a non-Western power's success.

Evaluated as a political system, China under Xi Jinping has moved toward greater repression. The concentration of power in Xi's person, the elimination of presidential term limits, the crackdown in Xinjiang, the suppression of Hong Kong's autonomy, the surveillance state, and the silencing of dissent represent, on this reading, a fundamental challenge to the idea that human beings possess inherent rights that governments must respect.

Evaluated as an international actor, China's behaviour is simultaneously constructive and assertive. The Belt and Road Initiative provided infrastructure financing to developing nations that Western institutions had neglected. But China's territorial claims in the South China Sea, its debt-trap diplomacy (the claim, contested by some scholars, that BRI loans were designed to secure strategic assets when borrowers defaulted), and its growing military capability alarmed its neighbours.

The three evaluations are not easily reconciled. The development that improved hundreds of millions of lives was achieved under an authoritarian system. The international engagement that provided genuine benefits to developing nations also extended authoritarian influence. The challenge for analysis is to hold these dimensions simultaneously rather than reducing China to a single story.

COVID-19: a lens on national capacity and inequality

The pandemic functioned as a stress test for national institutions, revealing strengths and weaknesses that had previously been theoretical.

China's response demonstrated the capacity of an authoritarian system to implement drastic measures rapidly. The initial lockdown of Wuhan and later the zero-COVID policy restricted individual freedom on a scale that would have been impossible in a democracy. The approach contained the virus effectively for extended periods but at enormous social cost and with increasing public frustration.

The United States' response demonstrated the costs of political polarisation. Public health measures became partisan identity markers. Vaccination rates diverged sharply by political affiliation. The country with the most advanced biomedical research infrastructure in the world also had one of the highest per capita death rates among wealthy nations. The gap between scientific capacity and institutional effectiveness was stark.

India's response demonstrated the vulnerability of systems with large informal economies, limited healthcare infrastructure, and dense urban populations. The lockdown caused immediate economic devastation for millions of daily-wage workers. The second wave overwhelmed systems that had seemed to be managing. The gap between the India of the technology sector and the India of the migrant worker was laid bare.

African nations, contrary to many early predictions, experienced lower reported mortality than expected. Explanations included younger populations, fewer nursing homes, experience with previous epidemics that produced functional public health infrastructure, and possible cross-immunity from other coronaviruses. But limited testing and weak vital registration systems meant that the true toll was uncertain.

The pandemic's unequal impact mirrored pre-existing inequalities within and between nations. Essential workers, often from minority or marginalised communities, faced greater exposure. Women bore disproportionate burdens of caregiving. Students without reliable internet access fell behind in remote learning. The pandemic did not create these inequalities. It revealed and intensified them.

Advanced analysis: interconnected crises Master

The digital-climate nexus

The digital revolution and the climate crisis are interconnected in ways that standard analyses often miss. The infrastructure of the digital economy, data centres, server farms, cryptocurrency mining, and the manufacturing of electronic devices, consumes enormous amounts of energy. Training a single large AI model can produce carbon emissions equivalent to the lifetime emissions of several automobiles. The production of smartphones and other devices requires the mining of rare earth minerals under conditions that are often environmentally destructive and exploitative of workers.

At the same time, digital technology offers tools for addressing climate change: smart grids, precision agriculture, climate modelling, remote sensing for deforestation monitoring, and platforms for coordinating collective action. The relationship between the digital and climate revolutions is not simply one of cause and effect. It is one of mutual reinforcement and mutual tension.

The security-migration nexus

The refugee crises of the 21st century are not independent events. They are connected to the War on Terror, to climate change, to the Arab Spring, and to the economic structures of globalisation. The Syrian refugee crisis was produced by a civil war that resulted from the Arab Spring. The Central American migration crisis was shaped by American foreign policy in the 1980s, the drug war, and economic policies that displaced rural communities. The Rohingya crisis was produced by ethno-nationalism enabled by democratic backsliding.

Climate change is expected to produce far larger displacement in the coming decades. The World Bank estimated in 2021 that climate change could force 216 million people to migrate within their own countries by 2050. These climate migrants will join the existing flows of refugees and economic migrants, straining the international system's already inadequate frameworks for managing displacement.

The technology-democracy nexus

The relationship between digital technology and democratic governance is ambivalent. Social media enabled the Arab Spring, the Black Lives Matter movement, and the #MeToo movement. It gave voice to people who had been excluded from traditional media. It facilitated collective action on a scale that was previously impossible.

The same technology enabled disinformation, foreign interference in elections, the amplification of extremist content, and the construction of surveillance states. The attention economy rewarded outrage over deliberation. Algorithmic feeds created filter bubbles that reinforced existing beliefs. The result was a public sphere that was simultaneously more participatory and more fragmented than at any point in modern history.

Connections Master

• Cold War 32.24.01. The War on Terror inherited structures, alliances, and habits of thought from the Cold War. The CIA's support for the mujahideen in Afghanistan during the 1980s, discussed in unit 32.24.01, directly produced the conditions that led to 9/11 and the subsequent American invasion. The Cold War framework of containment, which interpreted every conflict through the lens of a global ideological struggle, was repurposed for the War on Terror, with similar results: local conflicts were absorbed into a global narrative, local actors were reduced to proxies, and the people who actually lived in the conflict zones suffered the consequences.

• Decolonization 32.23.01. The borders, institutions, and economic structures created during the colonial era and maintained through the Cold War continued to shape the 21st century. The Middle Eastern borders drawn by Britain and France after World War I, discussed in unit 32.23.01, produced states whose legitimacy was contested, providing the conditions for both authoritarian rule and popular uprising. The economic inequality between the Global North and the Global South that made climate injustice possible was itself a product of centuries of extraction.

• Industrial Revolution 32.18.01. The climate crisis is a consequence of the industrialisation that began in Britain in the late 18th century. The fossil fuel economy that the Industrial Revolution created, discussed in unit 32.18.01, produced the emissions that are now warming the planet. The same process that generated unprecedented wealth for some also generated an existential threat for others.

• Colonialism and imperialism 32.15.01. The patterns of Western military intervention in the Global South that characterised the War on Terror reproduced dynamics established during the colonial era. The assumption that Western powers had the right and the obligation to reshape the political systems of non-Western nations, discussed in unit 32.15.01, persisted from the colonial era through the Cold War and into the 21st century.

• Atlantic slave trade 32.16.01. The racial justice movements of the 21st century, including Black Lives Matter, were rooted in the legacy of the Atlantic slave trade and the systems of racial hierarchy it created. The unit 32.16.01 describes how the slave trade produced ideologies of racial difference that outlasted abolition and continued to shape institutions, policing, and economic inequality in the 21st century.

• Globalization 32.25.01. The interconnected crises of the 21st century, from pandemics to climate change to refugee flows to financial crises, were amplified by the very globalisation that was supposed to produce universal prosperity. The supply chains, migration patterns, communication networks, and financial systems described in unit 32.25.01 transmitted shocks rapidly across borders, making every crisis a global crisis.

Historical and philosophical context Master

The end of the "end of history"

Francis Fukuyama's 1989 essay "The End of History?" argued that the collapse of communism and the triumph of liberal democracy represented the endpoint of ideological evolution. Humanity had arrived at the optimal form of political organisation. The remaining struggles were practical, not ideological.

The 21st century demolished this thesis. The rise of China demonstrated that authoritarian capitalism could deliver economic development without political freedom. Democratic backsliding in Hungary, Turkey, the Philippines, Brazil, and the United States showed that democratic institutions were more fragile than assumed. The Arab Spring and its aftermath revealed that the desire for democracy was genuine but that its achievement was far from inevitable.

The end of the "end of history" thesis was itself a historical development. It reflected the recognition that the post-Cold War optimism of the 1990s was a product of specific circumstances, the unipolar moment of American dominance, rather than a permanent condition.

Climate change and the failure of imagination

Amitav Ghosh, in The Great Derangement (2016), argued that the climate crisis represented a failure not of technology or policy but of imagination. The literary and cultural forms of the modern era, the novel, realism, the assumption of a stable backdrop against which human drama unfolds, were inadequate to a reality in which the backdrop was itself the story. The climate crisis was not merely a policy problem. It was a civilisational challenge that required new ways of thinking about humanity's relationship with the natural world.

Naomi Klein, in This Changes Everything (2014), argued that the climate crisis was inseparable from the economic system that produced it. Capitalism's requirement for endless growth on a finite planet was, on this reading, the structural cause of climate change. Addressing the crisis required not merely technological substitution but a fundamental restructuring of economic priorities.

The historiography of the present

Writing the history of the present poses distinctive challenges. The sources are overwhelming in volume but incomplete in perspective. Digital communication produces vast archives of social media posts, government emails, corporate records, and satellite imagery, but these archives reflect the biases of their creators and the limitations of their platforms. Many of the key actors are still alive and active, making independent assessment difficult. The outcomes are unknown. The historian of the 21st century is writing about a story whose ending has not been written.

The multi-perspective approach adopted in this unit is both a methodological choice and an ethical one. No single narrative can capture the experience of a century that is being lived differently by billions of people. The American experience of 9/11, the Afghan experience of the War on Terror, the Pacific Island experience of climate change, the Syrian experience of civil war, the Chinese experience of rapid development: these are not perspectives that can be merged into a single account. They must be held in tension.

The Anthropocene and deep time

The concept of the Anthropocene, proposed by Paul Crutzen in 2000 and developed by the Working Group on the Anthropocene, locates the present within geological time. The radioactive isotopes from nuclear weapons testing, the plastic particles deposited in ocean sediments, the carbon dioxide concentrated in the atmosphere: these will be detectable in the geological record for millions of years. The 21st century will be legible to geologists of the distant future as the moment when a single species acquired the capacity to alter the planet's fundamental systems.

This temporal framing reframes political and economic debates. Disputes about emissions targets and economic growth that seem pressing on a political timescale of years and decades appear different when placed on a geological timescale of millennia. The Anthropocene asks what it means to exercise the power to shape the planet and whether the institutions developed over the past few centuries are adequate to the responsibility.

Bibliography Master

Primary sources and official reports:

• IPCC. Climate Change 2023: Synthesis Report. Intergovernmental Panel on Climate Change, 2023.
• The 9/11 Commission Report. W.W. Norton, 2004.
• The Iraq Inquiry (Chilcot Report). UK Government, 2016.
• UNFCCC. Paris Agreement. United Nations, 2015.
• UNHCR. Global Trends: Forced Displacement in 2023. United Nations High Commissioner for Refugees, 2024.
• WHO. COVID-19 Weekly Epidemiological Updates. World Health Organization, 2020-2023.
• Snowden, Edward. Permanent Record. Metropolitan Books, 2019.
• BRICS. Fortaleza Declaration. 6th BRICS Summit, 2014.
• Xi Jinping. The Governance of China. Foreign Languages Press, 2014-2022 (3 vols).

Modern scholarship:

• Crutzen, Paul J. "The Anthropocene." In Earth System Science in the Anthropocene, edited by Ehlers and Krafft, 13-18. Springer, 2006.
• Fukuyama, Francis. "The End of History?" The National Interest 16 (Summer 1989): 3-18.
• Ghosh, Amitav. The Great Derangement: Climate Change and the Unthinkable. University of Chicago Press, 2016.
• Klein, Naomi. This Changes Everything: Capitalism vs. The Climate. Simon and Schuster, 2014.
• Levitsky, Steven, and Daniel Ziblatt. How Democracies Die. Crown, 2018.
• Milanovic, Branko. Global Inequality: A New Approach for the Age of Globalization. Harvard University Press, 2016.
• Mounk, Yascha. The People vs. Democracy. Harvard University Press, 2018.
• Runciman, David. How Democracy Ends. Profile Books, 2018.
• Tooze, Adam. Shutdown: How Covid Shook the World's Economy. Allen Lane, 2021.
• Westad, Odd Arne. The Cold War: A World History. Basic Books, 2017.
• Zuboff, Shoshana. The Age of Surveillance Capitalism. PublicAffairs, 2019.