- Jan 29 US President George W. Bush in his State of the Union address describes "regimes that sponsor terror" an "Axis of Evil", which includes Iraq, Iran and North Korea
- Mar 2 U.S. invasion of Afghanistan: Operation Anaconda begins, (ends March 19 after killing 500 Taliban and al Qaeda fighters, with 11 Western troop fatalities).
- May 12 Former US President Jimmy Carter arrives in Cuba for a five-day visit with Fidel Castro becoming first President of the United States, in or out of office, to visit the island since Castro's 1959 revolution.
- Jun 6 A near-Earth asteroid estimated at 10 metres diameter explodes over the Mediterranean Sea between Greece and Libya. Resulting explosion estimated to have a force of 26 kilotons, more powerful than the Nagasaki atomic bomb.
- Jul 9 The African Union is established in Addis Ababa, Ethiopia. The first chairman is Thabo Mbeki, President of South Africa.
- Nov 8 Iraq disarmament crisis: UN Security Council under Resolution 1441 unanimously approves a resolution on Iraq, forcing Saddam Hussein to disarm or face "serious consequences"
- Dec 13 Enlargement of the European Union: The European Union announces that Cyprus, the Czech Republic, Estonia, Hungary, Latvia, Lithuania, Malta, Poland, Slovakia, and Slovenia will become members from May 1, 2004.
The first public version of the web browser Mozilla Firefox ("Phoenix 0.1") is released
On September 23, 2002