The rationale for the Iraq War, both the 2003 invasion of Iraq and the subsequent hostilities, was controversial. The George W. Bush administration began actively pressing for military intervention in Iraq in late 2001. The primary rationalization for the Iraq War was articulated by a joint resolution of the United States Congress known as the Iraq Resolution. The US claimed the intent was to "disarm Iraq of weapons of mass destruction, to end Saddam Hussein's support for terrorism, and to free Iraqi people".
In the lead-up to the invasion, the United States and the United Kingdom claimed that Saddam Hussein was developing weapons of mass destruction and that he thus presented a threat to his neighbors and to the world community. The US stated, "on November 8, 2002; the UN Security Council unanimously adopted Resolution 1441. All 15 members of the Security Council agreed to give Iraq a final opportunity to comply with its obligations and disarm or face the serious consequences of failing to disarm. The resolution strengthened the mandate of the UN Monitoring and Verification Commission (UNMOVIC) and the International Atomic Energy Agency (IAEA), giving them the authority to go anywhere, at any time, and talk to anyone in order to verify Iraq's disarmament." Throughout late 2001, 2002, and early 2003, the Bush administration worked to build a case for invading Iraq, culminating in then-Secretary of State Colin Powell's February 2003 address to the Security Council. Shortly after the invasion, the Central Intelligence Agency, Defense Intelligence Agency, and other intelligence agencies largely discredited evidence related to Iraqi weapons as well as alleged links to al-Qaeda, and at this point, the Bush and Blair administrations began to shift to secondary rationales for the war, such as the Saddam Hussein government's human rights record and promoting democracy in Iraq. Opinion polls showed that people of nearly all countries opposed a war without a UN mandate and that the perception of the United States as a danger to world peace had significantly increased. UN Secretary-General Kofi Annan described the war as illegal, saying in a September 2004 interview that it was "not in conformity with the Security Council".
Accusations of faulty evidence and alleged shifting rationales became the focal point for critics of the war, who charge that the Bush administration purposely fabricated evidence to justify an invasion that it had long planned to launch. The US led the effort for "the redirection of former Iraqi weapons of mass destruction (WMD) scientists, technicians, and engineers to civilian employment and discourage emigration of this community from Iraq".
The United States officially declared its combat role in Iraq over on 31 August 2010, although several thousand troops remained in the country until all American troops were withdrawn from Iraq by December 2011; meanwhile, American troops also engaged in combat with Iraqi insurgents. In June 2014, however, US forces returned to Iraq due to an escalation of instability in the region, and in June 2015, the number of American ground troops totaled 3,550. Between December 2011 and June 2014, Department of Defense officials estimated that there were 200 to 300 personnel based at the US embassy in Baghdad.
Background
The Gulf War never fully ended because no armistice formally ended it. As a result, relations between the United States, the United Nations, and Iraq remained strained, although Saddam Hussein issued formal statements renouncing his invasion of Kuwait and made reparations payments. The US and the United Nations maintained a policy of "containment" towards Iraq, which involved economic sanctions, Iraqi no-fly zones enforced by the United States, United Kingdom, and France (until it ended its no-fly zone operations in 1998) and ongoing inspections of Iraqi weapons programs. In 2002, the UN Security Council unanimously passed Resolution 1441 demanding that Iraq "comply with its disarmament obligations" and allow weapons inspections. Iraq war critics such as former weapons inspector Scott Ritter claimed that these sanctions and weapons inspections policies, supported by both the Bush and Clinton administrations, were actually intended to foster regime change in Iraq.