Estimated deaths: Lancet survey** (March 2003 – July 2006): 654,965 (95% CI: 392,979–942,636) Iraq Family Health Survey*** (March 2003 – July 2006): 151,000 (95% CI: 104,000–223,000) PLOS Medicine Study**: (March 2003 – June 2011): 405,000 (95% CI: 48,000–751,000), in addition to 55,000 deaths missed due to emigration.
Documented deaths from violence: Iraq Body Count (2003 – 14 December 2011): 103,160–113,728 civilian deaths recorded, and 12,438 new deaths added from the Iraq War Logs Associated Press(March 2003 – April 2009): 110,600
* "injured, diseased, or other medical": required medical air transport. UK number includes "aeromed evacuations". **Total excess deaths include all additional deaths due to increased lawlessness, degraded infrastructure, poorer healthcare, etc. ***Violent deaths only – does not include excess deaths due to increased lawlessness, poorer healthcare, etc.
The Bush administration based its rationale for the war principally on the assertion that Iraq, which had been viewed by the U.S. as a rogue state since the 1990–1991 Gulf War, possessed weapons of mass destruction (WMDs), along with concerns about an active WMD program, and that the Iraqi government posed a threat to the United States and its coalition allies. Select U.S. officials accused Saddam of harbouring and supporting al-Qaeda, while others cited the desire to end a repressive dictatorship and bring democracy to the people of Iraq. Hundreds of chemical weapons were found in Iraq, which were determined to be produced before the 1991 Gulf War, and intelligence officials determined they were "so old they couldn't be used as designed." From 2004 to 2011, US troops and American-trained Iraqi troops repeatedly encountered, and on six reported occasions were wounded by, chemical weapons from years earlier in Saddam Hussein's rule. Roughly 5,000 chemical warheads, shells or aviation bombs were discovered. The rationale of U.S. pre-war intelligence faced heavy criticism both domestically and internationally. From 2009 to 2011, the UK conducted a broad inquiry into its decision to go to war chaired by Sir John Chilcot. The Chilcot Report, published in 2016, concluded military action may have been necessary but was not the last resort at the time and that the consequences of invasion were underestimated.
In the aftermath of the invasion, Iraq held multi-party elections in 2005. Nouri al-Maliki became Prime Minister in 2006 and remained in office until 2014. The al-Maliki government enacted policies that were widely seen as having the effect of alienating the country's Sunni minority and worsening sectarian tensions. In the summer of 2014, the Islamic State of Iraq and the Levant (ISIL) launched a military offensive in Northern Iraq and declared a worldwide Islamic caliphate, eliciting another military response from the United States and its allies. The Iraq War caused over a hundred thousand civilian deaths and tens of thousands of military deaths (see estimates below). The majority of deaths occurred as a result of the insurgency and civil conflicts between 2004 and 2007.
Strong international opposition to the Saddam Hussein regime began after Iraq's invasion of Kuwait in 1990. The international community condemned the invasion, and in 1991 a military coalition led by the United States launched the Gulf War to expel Iraq from Kuwait. Following the Gulf War, the US and its allies tried to keep Saddam in check with a policy of containment. This policy involved numerous economic sanctions by the UN Security Council; the enforcement of Iraqi no-fly zones declared by the US and the UK to protect the Kurds in Iraqi Kurdistan and Shias in the south from aerial attacks by the Iraqi government; and ongoing inspections to ensure Iraq's compliance with United Nations resolutions concerning Iraqi weapons of mass destruction.
A UN weapons inspector in Iraq, 2002
The inspections were carried out by the United Nations Special Commission (UNSCOM). UNSCOM, in cooperation with the International Atomic Energy Agency, worked to ensure that Iraq destroyed its chemical, biological, and nuclear weapons and facilities. In the decade following the Gulf War, the United Nations passed 16 Security Council resolutions calling for the complete elimination of Iraqi weapons of mass destruction. Member states communicated their frustration over the years that Iraq was impeding the work of the special commission and failing to take seriously its disarmament obligations. Iraqi officials harassed the inspectors and obstructed their work, and in August 1998 the Iraqi government suspended cooperation with the inspectors completely, alleging that the inspectors were spying for the US. The spying allegations were later substantiated.
In October 1998, removing the Iraqi government became official U.S. foreign policy with enactment of the Iraq Liberation Act. The act provided $97 million for Iraqi "democratic opposition organizations" to "establish a program to support a transition to democracy in Iraq." This legislation contrasted with the terms set out in United Nations Security Council Resolution 687, which focused on weapons and weapons programs and made no mention of regime change. One month after the passage of the Iraq Liberation Act, the US and UK launched a bombardment campaign of Iraq called Operation Desert Fox. The campaign's express rationale was to hamper Saddam Hussein's government's ability to produce chemical, biological, and nuclear weapons, but U.S. intelligence personnel also hoped it would help weaken Saddam's grip on power.
With the election of George W. Bush as president in 2000, the US moved towards a more aggressive Iraq policy. The Republican Party's campaign platform in the 2000 election called for "full implementation" of the Iraq Liberation Act as "a starting point" in a plan to "remove" Saddam. However, little formal movement towards an invasion occurred until the 11 September attacks.