George W. Bush was the President of the United States from 2001 to 2009.

Operation Enduring Freedom was the name of the military operation launched by the United States in Afghanistan following the 9/11 attacks.

Operation Iraqi Freedom was the name of the military operation launched by the United States in Iraq in 2003.

Al-Qaeda was the terrorist organization responsible for the 9/11 attacks.

The Patriot Act was the law passed by the United States Congress in 2001 in response to the 9/11 attacks.

The Great Recession was the name of the economic recession that occurred in the United States from 2007 to 2009.

Lehman Brothers was the financial institution that collapsed in 2008, triggering the Great Recession.

The American Recovery and Reinvestment Act was the program enacted by the United States government in 2009 to help stimulate the economy during the Great Recession.

The Affordable Care Act was the health care reform law passed by the United States Congress in 2010.

National Federation of Independent Business v. Sebelius was the Supreme Court case that upheld the Affordable Care Act in 2012.

The Deepwater Horizon oil spill was the environmental disaster that occurred in the Gulf of Mexico in 2010.

Columbia was the space shuttle that disintegrated during re-entry into the Earth's atmosphere in 2003.

Katrina was the hurricane that devastated New Orleans and the Gulf Coast in 2005.

The 7/7 bombings were the terrorist attacks that occurred in London in 2005.

The Mumbai attacks were the terrorist attacks that occurred in Mumbai in 2008.