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How did the September 11 attacks and the challenges of the new century reshape the United States and its role in the world?

Topic 9.6 Challenges of the 21st Century: the post-Cold War world, the September 11 attacks and the War on Terror, the wars in Afghanistan and Iraq, the financial crisis, and growing political polarization.

A focused answer to AP US History Topic 9.6, covering the challenges of the new century: the post-Cold War world and the Persian Gulf War, the September 11 attacks and the War on Terror, the wars in Afghanistan and Iraq, the 2008 financial crisis, the election of Barack Obama, and rising political polarization.

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  1. What this topic is asking
  2. The post-Cold War world
  3. September 11 and the War on Terror
  4. The home front and civil liberties
  5. A century of crisis and division
  6. Worked example: arguing 9/11 changed American policy
  7. Try this

What this topic is asking

Topic 9.6 asks you to explain the challenges of the early twenty-first century: the post-Cold War world and the Persian Gulf War, the September 11 attacks and the War on Terror, the wars in Afghanistan and Iraq, the financial crisis of 2008, the election of Barack Obama, and rising political polarization. The exam wants how 9/11 and the new century's challenges reshaped the nation and its role in the world.

The post-Cold War world

September 11 and the War on Terror

The home front and civil liberties

The War on Terror reshaped life at home. The government greatly expanded security and surveillance, creating the Department of Homeland Security and passing the Patriot Act, which broadened government powers to monitor and detain. These measures reignited an old American debate over the balance between security and civil liberties, echoing earlier wartime crackdowns from the Espionage Act to Japanese American internment. The tension between protecting the nation and preserving freedom became, once again, a central question, one the exam often asks students to connect across periods.

A century of crisis and division

Worked example: arguing 9/11 changed American policy

Try this

Q1. Name the 2001 terrorist attacks that launched the War on Terror. [Recall]

  • Cue. The September 11 attacks, carried out by al-Qaeda.

Q2. Explain how the September 11 attacks reshaped both foreign and domestic policy. [Short explanation]

  • Cue. Abroad, the attacks led the United States to launch a War on Terror, invading Afghanistan in 2001 and Iraq in 2003; at home, the government expanded security and surveillance through the Patriot Act and new agencies, which reignited the long-running debate over how to balance national security against civil liberties.

Exam-style practice questions

Practice questions written in the style of College Board exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.

AP USH (style)3 marksBriefly describe ONE challenge the United States faced in the early twenty-first century. Briefly explain ONE government response to it. Briefly explain ONE lasting effect of that challenge.
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A Short Answer Question (SAQ), 3 points, one per bullet.

A. Describe: the September 11, 2001, terrorist attacks killed nearly 3,000 people and shocked the nation.

B. Response: the United States launched a War on Terror, invading Afghanistan in 2001 and Iraq in 2003 and expanding security and surveillance at home.

C. Effect: the wars proved long and costly, and debates over security versus civil liberties and over America's global role have continued.

Markers want a real challenge, a concrete response, and a genuine lasting effect.

AP USH (style)6 marksEvaluate the extent to which the September 11 attacks changed United States foreign and domestic policy in the period 2001 to 2010.
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A Long Essay Question (LEQ), scored on the 6-point rubric.

Thesis (1): "The September 11 attacks profoundly changed American policy, launching a War on Terror, two long wars, and an expansion of security and surveillance at home, though they also revived older debates over intervention and civil liberties."

Contextualization (1): the post-Cold War world in which the United States was the sole superpower.

Evidence (2): the wars in Afghanistan and Iraq; expanded domestic security such as the Patriot Act and the debate over civil liberties.

Analysis (2): explain HOW 9/11 reshaped foreign and domestic policy, then add complexity by weighing continuities in American debates over intervention and liberty.

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