Iraq War

Operation Iraqi Freedom began on 19 March 2003^[1] with U.S. and British air strikes on Baghdad followed by a ground invasion from Kuwait. The conventional regime-collapse phase ended in roughly three weeks; the statue of Saddam Hussein in Firdos Square came down on 9 April, and the Bush administration declared "Mission Accomplished" aboard the USS Abraham Lincoln on 1 May. The war's stated rationale combined three elements: that Iraq retained or was reconstituting weapons of mass destruction in violation of U.N. resolutions; that Saddam's regime had operational links to al-Qaeda relevant to post-9/11 counter-terrorism; and that the regime's character and conduct made regime change a defensible American objective in its own right. The first rationale collapsed when the U.S.-led Iraq Survey Group reported in 2004 that no WMD stockpiles existed; the second was never substantiated by the intelligence community.

The longer trajectory ran through the unfinished 1991 war. The Iraq sanctions regime had degraded Iraqi state capacity through the 1990s without dislodging Saddam; the Iraq Liberation Act of 1998^[1] had made regime change formal U.S. policy under Clinton; Saddam's expulsion of UNSCOM weapons inspectors that year, followed by Operation Desert Fox bombing, left the WMD question unresolved. After 11 September 2001, the neoconservative wing of the Bush administration — Vice President Dick Cheney, Secretary of Defense Donald Rumsfeld, Deputy Secretary Paul Wolfowitz, and others — elevated Iraq from a long-running problem to an acute one. The October 2002 National Intelligence Estimate on Iraqi WMD presented conclusions with greater confidence than the underlying evidence supported; Secretary of State Colin Powell's 5 February 2003 U.N. presentation made the case publicly. The U.N. Security Council declined to authorize war in a second resolution; the coalition (substantially smaller than 1991's) went without U.N. cover.

The strategic theory behind the war combined containment logic with a more ambitious claim that democratizing Iraq would catalyze democratization across the Middle East and reduce the conditions producing transnational terrorism — a "freedom agenda" expressed in Bush's January 2002 "Axis of Evil" State of the Union and the September 2002 National Security Strategy. The State Department's multi-volume "Future of Iraq" planning was largely sidelined by Pentagon-led occupation planning that anticipated a substantially shorter and lighter American presence than the war actually required.

Saddam Hussein's regime fell; U.S. forces withdrew in 2011, but instability and later conflict persisted.

Two early decisions by the Coalition Provisional Authority under L. Paul Bremer shaped the insurgency that followed. CPA Order Number 1 (16 May 2003)^[1] banned the top four ranks of the Ba'ath Party from public employment, removing tens of thousands of trained administrators and teachers. CPA Order Number 2 (23 May)^[1] dissolved the Iraqi Army, Republican Guard, and Ministry of Defense, putting roughly 400,000 trained men with weapons and military networks onto the streets without pay or pension. The Sunni insurgency that intensified through 2004 — and the Shia militia response — drew on both populations. The April 2004 publication of photographs from the Abu Ghraib prison made the war's moral cost legible globally and damaged the American case for the war among allies and at home. By 2006 the country was in a sectarian civil war with monthly civilian death tolls in the thousands. The 2007 surge under General David Petraeus, combined with the Anbar Awakening of Sunni tribes against al-Qaeda in Iraq, reduced violence sharply but did not produce the political reconciliation it was supposed to enable.

The U.S. troop drawdown completed in December 2011^[2] under President Obama, after the Status of Forces Agreement negotiated by the Bush administration expired without a successor agreement. Prime Minister Nouri al-Maliki's marginalization of Sunni political participation, combined with the Syrian civil war that broke out in 2011, produced the conditions in which the Islamic State of Iraq and the Levant (ISIS) seized Mosul and much of western Iraq in 2014^[2]. The second American intervention (Operation Inherent Resolve, 2014–2021) eventually defeated ISIS as a territorial entity at substantial additional cost. Total direct U.S. military deaths from the 2003–2011 war reached roughly 4,400, with ~32,000 wounded^[3]; Iraq Body Count documents over 200,000 Iraqi civilian deaths through 2021 with higher estimates from other methodologies.

The strategic results were largely the opposite of those the war's planners had projected. Iraq did not catalyze regional democratization; it produced a fragile Shia-led government oriented toward Iran. Iranian regional influence grew substantially as the Sunni Arab counterweight Iraq had provided was removed. The war's refugee outflows and sectarian polarization contributed to the conditions in which ISIS expanded into Syria after 2013 and into Europe through the 2015 migration crisis. American domestic politics absorbed the war's costs through Barack Obama's 2008 election (partly built on his 2002 antiwar position) and, more disruptively, through Donald Trump's 2016 election (partly built on rejecting the foreign-policy consensus the war had discredited). The Costs of War Project at Brown University estimates the total American fiscal cost of the Iraq war, inclusive of future veteran care, at roughly $2.9 trillion.