Iraq, which has fallen out of the spotlight since the December 2011 U.S. troop withdrawal, has been plagued by rising internal conflict and instability. On Monday, al-Qaeda terrorists launched a brazen attack on two prisons near Baghdad and freed more than 500 prisoners.

While the world’s attention has been focused on violent clashes in Syria and Egypt, Iraq has been slipping back toward civil war. Violence in Iraq has returned to levels not seen since the U.S. troop surge and the Anbar Awakening—the turning of Sunni Arab tribes against al-Qaeda in Iraq (AQI) in Anbar province—began to stem the tide of insurgency in 2007–2008.

According to the most recent casualty figures compiled by the United Nations, 554 civilians and 204 security troops were killed in June, down from the 1,045 killed in May, which was the bloodiest month in Iraq in five years. The casualty toll has been boosted by the resurgence of AQI, rising sectarian tensions between Sunnis and Shias and between Muslims and Christians, as well as clashes among Kurds, Arabs, and Turkmen over territorial disputes in northern Iraq.

The Iraqi government has been a factor in the growing violence. Iraqi Prime Minister Nouri al-Maliki, a Shiite Islamist, has acted to maximize his own power and that of his Shia allies at the expense of Iraqi minorities, particularly Sunni Arabs and Kurds. After the final withdrawal of U.S. troops in December 2011, Maliki quickly moved against his Sunni rivals, tried to arrest his Sunni vice president, and consolidated his control over Iraqi security forces.

AQI had been severely degraded by 2011 in an intensive counterterrorism campaign launched by U.S. special operations forces and Iraqi security forces. Maliki’s aggressive political purges alienated Iraqi Sunnis who had previously turned against AQI and helped to polarize Iraqi politics in a manner that AQI exploited to rebuild its shattered strength.

The Obama Administration also deserves a share of the blame. After promising for years that it would conduct a responsible withdrawal of combat troops while leaving a residual U.S. troop presence for training and advising Iraqi forces, the Administration opted to pull the plug and remove military advisers in late 2011. This greatly weakened Iraq’s ability to keep the pressure on AQI and to limit Iran’s growing influence.

But President Obama glossed over the dangerous security implications of his decision and used it to boost his re-election prospects in a televised speech in which he proclaimed: “Today, I can say that our troops in Iraq will definitely be home for the holidays.”

Negotiations with the Iraqi government on extending the U.S. military presence stalled in large part because Iraqi leaders balked at taking political risks to approve an unpopular extension of immunity from prosecution for U.S. troops. It was clear to them that the Obama Administration was eager to exit Iraq and lacked the stomach to confront Iran, which has exerted growing influence over Iraq’s majority Shia political parties.

Heritage analysts warned repeatedly about the dangers of an abrupt and total withdrawal of U.S. troops. But the Obama Administration made a losing bet that Iraq’s stability and U.S. security interests could be protected with minimal U.S. participation. The growing carnage in Iraq makes a mockery of President Obama’s December 2011 statement that, after the U.S. pullout, Iraq would be “sovereign, stable and self-reliant.”