2001

• Sept. 13: White House blames Osama bin Laden for the attacks

• Sept. 20: President Bush announces creation of the Office of Homeland Security

• Oct. 5: Letters containing deadly anthrax are sent to NBC News, the New York Post, Senate Majority Leader Tom Daschle and Sen. Patrick Leahy

• Oct. 7: U.S. begins bombing Afghanistan, focusing on al-Qaida training camps and Taliban installations

• Oct. 26: Bush signs USA Patriot Act

• Dec. 22: Shoe bomber Richard Reid is arrested for trying to blow up a Miami-bound jet using explosives concealed in his shoe

2002

• Jan. 11: First 20 Afghan prisoners are transferred to Guantanamo Bay, Cuba

• May 20-24: Bush administration issues series of terror warnings, focusing on how al-Qaida terrorists may target apartment buildings, banks, trains and crowded monuments

• Sept. 12: White House releases 26-page document called "A Decade of Defiance and Deception," intended to show how Saddam Hussein has been and continues to be a threat to the U.S.

• Sept. 19: Iraqi Foreign Minister Naji Sabri tells the United Nations that Iraq does not have any chemical, biological or nuclear weapons

• Oct. 12: Car bomb kills 202 at a discotheque at Kuta Beach, on the Indonesian island of Bali

• Nov. 25: Homeland Security is made a department with Tom Ridge as secretary

• Nov. 28: Death toll hits 16 as suicide bombers target resort in Mombasa, Kenya

2003

• Feb. 15: Over one million people around the world gather to protest a possible war in Iraq

• March 18: Bush gives Saddam a deadline to leave Iraq or face military action

• March 19: Baghdad is attacked, and troops from the U.S., Britain, Australia and Poland invade Iraq

• April 19: U.S. troops take control of Baghdad

• May 1: Bush declares that "major combat operations" have ended

• July 24: Independent 9/11 commission releases 800-page report on its investigation into the terrorist attacks of 2001

• Dec. 13: U.S. troops capture Saddam in a small village near Tikrit

2004

• Jan. 17: Death toll of U.S. soldiers killed in Iraq since the war started reaches 500