I.

Introduction

U.S.-Iraq War, military action begun in 2003 with a United States invasion of Iraq, then ruled by the authoritarian regime of Saddam Hussein. The invasion led to a protracted U.S. occupation of Iraq and the birth of a guerrilla insurgency against the occupation. The resulting destabilization of Iraq also created conditions for a civil war to break out between Iraq’s majority Shia Muslim population and its minority Sunni Muslim population. In addition to attempting to quell the insurgency, U.S. forces also found themselves trying to police the civil war. By 2007 the U.S. war in Iraq had lasted longer than U.S. involvement in World War II.

U.S. president George W. Bush had openly threatened war for months prior to the U.S. invasion. Bush argued that in the aftermath of the September 11 attacks, Saddam Hussein’s regime posed a grave threat to U.S. security and peace in the region because of its alleged pursuit of weapons of mass destruction and links to international terrorism. Subsequent disclosures by former high-level officials within the Bush administration, however, revealed that Bush had been preparing for the use of military force against Iraq almost as soon as he took office in January 2001. (A call for the ouster of Hussein had been official U.S. policy ever since Congress passed, and President Bill Clinton signed, the Iraq Liberation Act in 1998, although passage of the act did not commit the United States to the use of military force.)

Bush launched the war with an invasion of Iraq on March 20, 2003. The previous day a U.S. air strike attempted but failed to assassinate Hussein. U.S. and British forces (and smaller numbers of Australian and Polish soldiers) invaded Iraq from Kuwait. They faced an Iraqi military of less than 400,000 troops, the backbone of which was ten armored and mechanized divisions. These divisions were quickly devastated by U.S. air attacks. Major combat engagements ended about three weeks later, after U.S. troops entered Baghdād, the capital of Iraq, and toppled the Hussein regime. The military campaign was short and one-sided, but hard fought.

In all, 138 U.S. service personnel were killed from the start of the war until President Bush declared an end to major combat operations on May 1, 2003. Of these, 115 died in combat while the rest died due to traffic accidents, drowning, illness, or other causes. However, coalition forces continued to suffer casualties after May 1 as an urban guerrilla resistance began to develop.

By late April 2003, a serious and persistent guerrilla struggle had been launched in the Sunni Arab heartland against the foreign military presence in the country. Abetted by a U.S. decision to dissolve the Iraqi army and the U.S. failure to stop widespread looting, the guerrilla movement grew in strength and popular support in the center-north of the country, making it impossible for the United States to withdraw most of its troops in summer and fall of 2003, as the Department of Defense had intended. See also Guerrilla Warfare.

The total U.S. military death toll had doubled by late August 2004 and reached more than 4,000 following the fifth anniversary of the invasion. The year 2007 was the deadliest year for U.S. forces since the war began, with 894 U.S. soldiers killed in that year alone. The number of U.S. wounded totaled about 30,000 by March 2008, the beginning of the sixth year of the U.S. occupation. Other member nations of the coalition that suffered casualties included the United Kingdom, Italy, Ukraine, Poland, Bulgaria, Spain, Slovakia, El Salvador, The Netherlands, Thailand, Denmark, Estonia, Hungary, Kazakhstan, Latvia, and Australia.

Tens of thousands, if not hundreds of thousands, of Iraqis have been killed in the war, although U.S. military officials do not publicly keep a count of Iraqi insurgent or civilian casualties. A number of studies and estimates of Iraqi civilian deaths have arrived at radically different figures. For example, the British-based Iraq Body Count, which bases its casualty figures on media reports, hospital records, and other sources, reported that the number of dead Iraqi civilians ranged from 82,000 to 90,000 by March 2008. The deaths were of noncombatants killed by military or paramilitary forces. However, a year earlier, in October 2006, a study published in a British medical journal, The Lancet, by a team of U.S. epidemiologists and Iraqi physicians estimated that about 655,000 people had died in Iraq as a result of the war, with about 600,000 deaths directly attributable to violence.

Both the U.S. and the Iraqi governments disputed the The Lancet study, but the researchers based at Johns Hopkins University defended their results. They said the study was based on a widely accepted scientific method known as cluster sampling and that a majority of the deaths in the sample were substantiated by death certificates. Similar cluster samples have been accepted as valid in other troubled regions, such as Darfur.

In January 2008, researchers with the World Health Organization and the Iraqi Ministry of Health in a study published in the New England Journal of Medicine estimated that 151,000 Iraqis, both civilians and fighters, died violently from March 2003 to June 2006. The study was reportedly the largest to date because it was based on a survey of 10,000 Iraqi households.

The war also led to a refugee crisis in Iraq. By the end of 2007 the Office of the United Nations High Commissioner for Refugees estimated that 2.3 million Iraqis had fled their country and another 2.3 million had been displaced from their homes within Iraq.