What years does AP US History Period 9 cover?

Period 9 covers 1980 to the present, the contemporary era. It is the most lightly weighted unit on the exam, falling in Unit 9 and accounting for roughly 4 to 6 percent of the multiple choice section, because the period is recent and still unfolding. The College Board notes that historical developments can begin before and extend beyond these approximate dates, so expect overlap with the conservative ferment of the 1970s at the start.

What was Reaganomics?

Reaganomics was the economic program of the Reagan administration, based on supply-side economics, the theory that cutting taxes, especially on businesses and high earners, would spur investment and growth. Reagan cut taxes sharply, deregulated business, and increased military spending. The economy grew, but the combination of tax cuts and defense spending produced large deficits, and the core entitlement programs such as Social Security and Medicare endured, so the federal government did not actually shrink.

Why did the Cold War end?

The Cold War ended between 1989 and 1991. Most historians emphasize internal Soviet weakness: the stagnant centrally planned economy and the reforms of Mikhail Gorbachev, glasnost and perestroika, which loosened control and exposed the system's failures. The fall of the Berlin Wall in 1989 and the dissolution of the Soviet Union in 1991 marked the end. American pressure and the arms race contributed, but the decisive cause was the collapse of the Soviet system from within.

How did September 11 change the United States?

The September 11, 2001, attacks by al-Qaeda killed nearly 3,000 people and launched a War on Terror. The United States invaded Afghanistan in 2001 and Iraq in 2003, both becoming long and costly wars. At home, the government expanded security and surveillance through the Patriot Act and new agencies, reigniting the debate over the balance between security and civil liberties. The attacks reshaped American foreign and domestic policy and revived long-running questions about intervention and liberty.

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AP US History Period 9 (1980 to the present): entering a new era unit guide

Q: What are the Key Concepts for AP US History Period 9?

There are three. Key Concept 9.1 is that a newly ascendant conservative movement achieved several political and policy goals while contending with resistance, covering Reagan and conservatism. Key Concept 9.2 is that the end of the Cold War and new challenges to U.S. leadership forced the nation to redefine its foreign policy and global role. Key Concept 9.3 is that new developments in science and technology, as well as demographic shifts, have reshaped American society and the nation's role in the world.

A complete unit guide to AP US History Period 9 (1980 to the present), entering a new era. Maps the College Board Key Concepts 9.1 to 9.3, walks through the conservative resurgence, the end of the Cold War, globalization, and the challenges of the new century, and links to the dot points and the paired quiz.

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What Period 9 is about
The College Board Key Concepts
The dot points in this unit
How Period 9 is tested
Study strategy for this unit
Pair this with the quiz

What Period 9 is about

AP US History Period 9 (1980 to the present) is the contemporary era, the most lightly weighted unit on the exam. It opens with a conservative resurgence: Ronald Reagan's election in 1980 brought to power a New Right that cut taxes, reduced regulation, and moved American politics to the right. The era's other great turning point was the end of the Cold War, as the fall of the Berlin Wall (1989) and the dissolution of the Soviet Union (1991) left the United States the world's sole superpower. The economy was transformed by globalization and a digital revolution, and society by a new wave of immigration. The optimism of the 1990s gave way to the September 11 attacks, the War on Terror, the financial crisis of 2008, and deepening political polarization. This guide maps the unit, then links to a dot point for each major topic.

The College Board Key Concepts

The CED organizes Period 9 around three Key Concepts. Anchor your study to them.

Key Concept 9.1: the conservative resurgence

A newly ascendant conservative movement achieved several political and policy goals while contending with resistance. This covers the rise of the New Right, the policies of Reagan (supply-side tax cuts, deregulation, the military buildup), the role of the religious right, and the limits of the conservative revolution, including the survival of the major entitlement programs. See Reagan and Conservatism.

Key Concept 9.2: the end of the Cold War and a new global role

The end of the Cold War and new challenges to U.S. leadership forced the nation to redefine its foreign policy and global role. This covers the renewed tensions of the early 1980s, Gorbachev's reforms, the fall of communism in Eastern Europe, the dissolution of the Soviet Union, and the post-Cold War world that culminated in the September 11 attacks and the War on Terror. See The End of the Cold War and Challenges of the 21st Century.

Key Concept 9.3: science, technology, and demographic change

New developments in science and technology, as well as demographic shifts, have reshaped American society and the nation's role in the world. This covers globalization, the shift from manufacturing to services and technology, the digital revolution, and the new wave of immigration from Latin America and Asia. See A Changing Economy and Globalization.

The dot points in this unit

Our complete coverage of Period 9, one page per major topic:

How Period 9 is tested

Period 9 is the most lightly weighted unit, so the exam tests it broadly rather than in fine detail, and questions often ask you to connect the era to earlier periods. Favorite DBQ and LEQ themes include the causes and effects of the conservative resurgence, the causes of the end of the Cold War, the impact of globalization and technology, and the September 11 attacks and the renewed debate over security versus civil liberties. Because the period is defined by clear cause-and-effect developments, it is especially suited to causation questions.

Study strategy for this unit

Track the three threads. The conservative resurgence at home, the end of the Cold War abroad, and the transformation of the economy and society by globalization and technology. Use them to organize the unit.
Weigh causes, do not just list them. Be ready to rank the causes of the conservative resurgence and of the end of the Cold War. See Causation in Period 9.
Pin the key dates. Reagan elected 1980, the Berlin Wall 1989, the Soviet collapse 1991, NAFTA 1994, September 11 2001, the Iraq War 2003, the financial crisis and Obama's election 2008.
Connect across periods. Link the conservative resurgence back to the backlash against the 1960s, and the security-versus-liberty debate back to earlier wartime crackdowns.
Drill the rubrics. Apply the technique from our guide on how to write the APUSH DBQ and LEQ.

Pair this with the quiz

Test your grasp of the contemporary era with the Period 9 quiz, then work through the dot points above and review the official Course and Exam Description at AP Central.

Sources & how we know this

AP United States History Course and Exam Description — College Board (2020)