🇺🇸ap us history review

September 11

Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examWritten by the Fiveable Content Team • Last updated September 2025

Definition

September 11 refers to the date in 2001 when a series of coordinated terrorist attacks were carried out by the extremist group al-Qaeda against the United States, resulting in the destruction of the Twin Towers of the World Trade Center in New York City and significant damage to the Pentagon in Arlington, Virginia. This pivotal event fundamentally changed U.S. foreign and domestic policies, leading to a global 'War on Terror' and significant shifts in national security strategies.

5 Must Know Facts For Your Next Test

  1. On September 11, 2001, four commercial airliners were hijacked by terrorists, with two crashing into the Twin Towers and one into the Pentagon; the fourth plane, United Airlines Flight 93, crashed in Pennsylvania after passengers attempted to regain control.
  2. The September 11 attacks resulted in nearly 3,000 deaths and thousands more injured, marking one of the deadliest days in American history.
  3. In response to the attacks, the U.S. launched military operations in Afghanistan to dismantle al-Qaeda and remove the Taliban from power.
  4. The aftermath of September 11 saw significant changes in U.S. domestic policies, including increased airport security measures and the implementation of widespread surveillance practices.
  5. The event sparked a global wave of anti-terrorism efforts and alliances, influencing foreign relations and leading to conflicts that persist today.

Review Questions

  • How did the September 11 attacks influence U.S. foreign policy in the years that followed?
    • The September 11 attacks had a profound impact on U.S. foreign policy, leading to the initiation of the War on Terror, which included military interventions in Afghanistan and Iraq. The U.S. sought to dismantle al-Qaeda's network and remove regimes perceived as threats to its national security. This shift marked a move towards preemptive strikes and increased military engagement abroad, shaping America's role on the global stage for years to come.
  • Evaluate the effectiveness of the measures implemented after September 11, such as the Patriot Act and the creation of Homeland Security, in enhancing national security.
    • The measures implemented after September 11, like the Patriot Act and the establishment of Homeland Security, aimed to strengthen national security by increasing surveillance capabilities and improving coordination among various security agencies. While these measures led to enhanced monitoring of potential threats and greater preparedness for terrorist activities, they also raised concerns about civil liberties and privacy rights. The balance between security and personal freedoms continues to be a topic of debate in American society.
  • Assess how September 11 reshaped public perception of terrorism and its implications for international relations in subsequent years.
    • The events of September 11 significantly altered public perception of terrorism, transitioning it from an abstract threat to a concrete reality that affected everyday life. This shift led to increased fear and vigilance regarding security threats domestically and internationally. Consequently, it influenced international relations as nations were compelled to collaborate more closely on counter-terrorism efforts, leading to new alliances while also exacerbating tensions with certain countries deemed supportive of extremist ideologies. The long-term implications include ongoing military engagements, refugee crises, and evolving geopolitical landscapes.

"September 11" also found in: