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in Iraq over on 31 August 2010, although several thousand troops remained in the country until all American troops were withdrawn from Iraq by December 2011; meanwhile, American troops also engaged in combat with Iraqi insurgents.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 1991 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. US policy shifted in 1998 when the United States Congress passed and President Bill Clinton signed the Iraq Liberation Act after Iraq terminated its cooperation with UN weapons inspectors the preceding August. The act made it official US policy to "support efforts to remove the regime headed by Saddam Hussein from power", although it also made clear that "nothing in this Act shall be construed to authorize or otherwise speak to the use of United States Armed Forces". This legislation contrasted with the terms set out in United Nations Security Council Resolution 687, which made no mention of regime change. One month after the passage of the "Iraq Liberation Act", the US and UK launched a bombardment of Iraq named Operation Desert Fox. The campaign's expressed rationale was to