The Iraq War began on March 19, 2003 with an invasion by US-led forces and ended on December 18, 2011 when the last US combat forces left the country. Although the eight-and-a-half year war was successful in dismantling the regime of Saddam Hussein, it has produced a host of legal issues in its wake. The legitimacy of the initial invasion, the trial and execution of Saddam Hussein, the myriad problems associated with facilitating democratic elections and a stable government, accusations of war crimes against all sides in the conflict and continuing unrest in the region all played a role in the legal implications of the Iraq War. Another facet of this conflict was its enormous human and economic cost. As of November 30, 2011, the Brookings Institute estimated that 4,486 American troops were killed, 32,226 American troops were wounded and 179 British troops died. Estimates of Iraqi civilian death tolls have reached 168,000 through 2016. Financially, the war is estimated to have cost the US approximately US$3 trillion in total economic loss. The Iraq War also created domestic and international controversies, plaguing the administrations of presidents George W. Bush and Barack Obama and leaving many unanswered legal questions. Long after the battlefield conflict ended in December 2011, the war's legacy continued to play out in courtrooms, legislatures and the international community.