Was it a mistake to withdraw U.S. troops from Iraq?

• Position: Debate

The United States and its allies went to war against Iraq in March 2003, with President George W. Bush accusing Iraqi dictator Saddam Hussein of harboring weapons of mass destruction. * Within a month, Hussein had been ousted. But rather than overseeing a quick shift to stable democratic rule, the U.S. was drawn into a long, bloody sectarian conflict between Iraq's Sunni and Shiite Muslims. After his election in 2008, President Obama vowed to bring American troops home, and in 2011 he withdrew the last U.S. forces. But sectarian fighting and bombings have continued. In 2014, the Sunni terrorist group ISIS (Islamic State of Iraq and Syria) took advantage of the chaos by seizing large swaths of territory in Iraq and Syria (see map, p. 27). With the U.S. now using airstrikes to fight ISIS, debate is growing about whether the U.S. withdrew its forces from Iraq prematurely.

YES In April 2011, when the White House was considering the withdrawal of American troops from Iraq, I asked that 10,000 to 15,000 troops be left there to ensure the gains made by our brave servicemen and women wouldn't be undone. Instead, President Obama chose to withdraw every last U.S. service member.

The abrupt departure of American soldiers, who had been instrumental in maintaining order and preventing the rise of radical groups, left a vacuum. As a result, a massive resurgence of radical Islam in the Middle East now threatens us both at home and abroad.

That's a far cry from the situation in 2009: A U.S. troop surge that began two years earlier had stabilized Iraq, and radical Islam had lost its momentum. The strong engagement of our military in the region had put Al Qaeda on the run and was a success both militarily and politically. At that point, ISIL was a small force with little reach, and Iraqis who wanted to live in peace were steadily reclaiming their lives.

Today, ISIL controls several major cities in Iraq and has a growing army of fighters. As the group has expanded, it's spread violence and chaos--the perfect conditions for the launch of devastating attacks against the U.S. This reversal comes as a direct result of President Obama's refusal to take the advice of military commanders in 2011 who recommended that 16,000 troops remain in Iraq.

The 3,500 U.S. troops currently there--who Obama begrudgingly sent back during the past few years as his failures became apparent--simply aren't enough. According to General Jack Keane, one of the architects of the 2007...