Q: Can Barack Obama do anything to stop Iraq imploding?

The belief that the United States is at least partly to blame for Iraq being torn asunder by sectarian conflict in the vacuum that has followed the withdrawal of American troops in 2011 has heaped pressure on President Obama to respond to the escalating violence in the country.

The threat of the extremist Sunni Muslim group the Islamic State of Iraq and Syria taking the Iraqi capital Baghdad, after seizing the second-largest city Mosul in the north, is adding to that pressure.

President Obama said he would decided “in the days ahead” whether to use military action to help Iraq’s Shia-led government fight a militant organisation formed out of an al-Qaeda linked group that wants to create an Islamic state in the region.

“This poses a danger to Iraq and its people and, given the nature of these terrorists, it could pose a threat eventually to American interests as well,” he said.

Advances by the militants have also stirred Shia-led Iran into action with reports that Tehran has deployed its elite Revolutionary Guard to help the Iraqi government of prime minister Nuri al-Maliki.

This creates a bizarre situation where the US and Iran, on opposite sides over Tehran's nuclear ambitions and aggression towards Israel, might find themselves on the same side with common interests in Iraq.

Violence

The prevailing wisdom in Washington is that the violence stems from President George W Bush’s decision to invade Iraq in 2003 and the toppling of Saddam Hussein’s Sunni-dominated regime, Maliki’s divisiveness among a Sunni minority and Mr Obama’s disengagement in his sharp foreign policy shift. Each is to blame to some degree.

In a nightmare scenario for a retreating president, the US cannot allow internal conflict to overwhelm Iraq after withdrawing its troops. Whether he likes it or not, past US involvement will force the president into action to help Iraq. It is still in part America’s mess to clean up.

The president’s most vociferous foreign policy critics, notably Republican Senator John McCain, have said the rise of militants could have been avoided if the US had kept troops in the country after 2011.

Mr Obama yesterday categorically ruled out putting American boots on the ground again in Iraq, saying that he had asked his advisers to “prepare a range of other options,” but warned that it could take “several days” to ensure any airstrikes would work.

Beyond military support, a long-term resolution will only come from Maliki including Sunnis in a unified Iraqi government. Mr Obama acknowledged this yesterday, saying that the US would not be “dragged back” into Iraq by taking military action and “keeping a lid on things” while political leaders failed to heal internal divisions.

The more pressing issue is to ensure that Maliki’s US-backed Iraqi government survives, and that looks like drawing Obama back into a fight he had no role in starting and wants desperately to leave behind.