2003 invasion of Iraq

The 2003 invasion of Iraq was the first stage of the Iraq War. The invasion began on 20 March 2003 and lasted just over one month, including 26 days of major combat operations. The invasion was conducted by a United States–led coalition of mainly American, British, Australian, and Polish troops.

According to US president George W. Bush and UK prime minister Tony Blair, the coalition aimed to disarm Iraq of weapons of mass destruction (WMDs)—nuclear, chemical, and biological weapons—and "free the Iraqi people" by deposing president Saddam Hussein, in turn ending his "support for terrorism". Before the invasion, United Nations (UN) inspectors in Iraq had found no evidence of Iraqi WMDs; US and British officials claimed they were still hidden, and posed an immediate threat to world peace.

The invasion was strongly opposed by some long-standing US allies, including Canada, France, Germany, and New Zealand. In 2004, UN secretary-general Kofi Annan called the invasion illegal under international law, as a breach of the UN Charter. On 15 February 2003, there were worldwide protests against the anticipated invasion of Iraq, including a rally of three million people in Rome which was the largest anti-war rally in history.

The invasion began with an airstrike on the Presidential Palace in Baghdad on 20 March 2003. The following day, coalition forces launched an incursion into Basra Governorate from their massing point close to the Iraqi–Kuwaiti border. While special forces launched an amphibious assault from the Persian Gulf to secure Basra and the surrounding petroleum fields, the main invasion army occupied southern Iraq, engaging in the Battle of Nasiriyah on 23 March. Massive air strikes across the country and against Iraqi command and control threw the defending army into chaos and prevented an effective resistance. On 26 March, the 173rd Airborne Brigade was airdropped near the northern city of Kirkuk, where they joined forces with Kurdish rebels and fought several actions against the Iraqi Army, to secure the northern part of the country.

The main body of coalition forces continued their drive into the heart of Iraq and were met with little resistance. Most of the Iraqi military was quickly defeated. On 9 April 2003, 22 days after the first day of the invasion, the capital city of Baghdad was captured by coalition forces after the six-day-long Battle of Baghdad. Other operations included the capture and occupation of Kirkuk on 10 April and the attack on and capture of Tikrit on 15 April. Saddam and the Iraqi central leadership went into hiding, as the coalition forces finished occupying the country. On 1 May, Bush declared the "end of major combat operations" in Iraq; this began the occupation phase of the Iraq War, in which coalition forces fought the Iraqi insurgency. Saddam was captured by US forces on 13 December 2003.