The decision to dissolve the Iraqi army robbed Baghdad’s post-invasion military of some of its best commanders and troops. Combined with sectarian strains that persist 12 years later, it also drove many of the suddenly out-of-work Sunni warriors into alliances with a Sunni insurgency that would eventually mutate into ISIS. Many former Iraqi military officers and troops, trained under Saddam, have spent the last 12 years in Anbar Province battling both U.S. troops and Baghdad’s Shi'ite-dominated security forces, Pentagon officials say.
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The U.S.-ordered dissolution of the Iraqi army was a major error. But it was compounded by former Shi'ite Prime Minister Nouri al-Malaki’s wholesale firing of Sunni commanders in favor of more compliant, if less competent, Shi'ites during his 2006-2014 tenure. That turned what was supposed to have been a national army into little more than a sectarian militia that took orders from the Prime Minister’s inner circle. “Malaki went into that army and pulled out all of its distinguished leaders, whose guys were devoted to them, and put in these cronies and hacks,” Keane said. “And those guys pocketed the money that was supposed to be used for training.”
So how did the Iraqi army come to dissolve? The Bush Administration tapped Paul Bremer to head the so-called Coalition Provisional Authority on May 11, 2003. Twelve days later, he issued an order wiping away the Iraqi military, with a pledge to build a new one from scratch, untainted by any ties to Saddam's regime. The army’s end quickly led to civil unrest, a growing insurgency and a U.S. occupation that would last eight years and cost the lives of 4,491 American troops.