For Obama, Iraq Move Is a Policy Reversal

President Was Early Opponent of Iraq War and Made a Campaign Pledge to End It.

President Barack Obama stepped in front of the cameras on Thursday to utter words he hoped he would never say as commander in chief.

“I’ve therefore authorized targeted airstrikes if necessary to help forces in Iraq,” Mr. Obama said in a statement from the White House. “Today America is coming to help.”

The return to military engagement in Iraq is a reversal for Mr. Obama, whose early opposition to the war that toppled Saddam Hussein, and his promise to end it, fueled his long-shot campaign for the White House.

It also puts a spotlight on what has become a familiar feature of the Obama presidency, in which the leader of the most powerful military in the world has become defined by his reluctance to use it.

“They’re very, very wary,” said Barry Pavel, a former defense official and director of the Brent Scowcroft Center on International Security at the Atlantic Council. “There are situations that will come up in the world where that wariness is tested in order to ensure that U.S. national security interests will be protected.”

Mr. Obama said the situation in Iraq was one of those. And as with other instances when Mr. Obama deployed U.S. military might, events forced his hand. “There is no decision that I take more seriously than the use of military force,” Mr. Obama said. “And I’ve been careful to resist calls to return time and again to our military.”

The White House held off ordering military strikes in Iraq for nearly two months as Islamic extremists took over large portions of the country and threatened the government in Baghdad, which requested U.S. help. in nature

Mr. Obama instead deployed military advisers to aid Iraqi forces and said any use of American force would depend on Iraqi leaders’ ability to form a government that was less sectarian in nature.

The political solution to address Iraq’s sectarian divisions hasn’t yet materialized.

“What we are dealing with is something that goes beyond just the question of Baghdad’s governance,” said Christopher Hill, a former U.S. ambassador to Iraq. “We’re dealing with forces there, specifically ISIS, that threaten a larger war in the Middle East.”

The last time Mr. Obama authorized military strikes was in Libya in March 2011. Even then, with the U.S. leading a coalition of nations, he showed himself to be a reluctant warrior.

Just as Mr. Obama touted the withdrawal of American forces from Iraq during his re-election campaign, White House officials initially pointed to the intervention in Libya as a model for the kinds of coalitions that could sustain a military intervention. A recent surge in violence there has quieted that view.

Mr. Obama and Vice President Joe Biden, whose son served in Iraq, pointed to the withdrawal of U.S. forces as part of their legacy. “We were able to turn lemons into lemonade here,” Mr. Biden said in a 2011 interview during his flight from Baghdad to Erbil on a trip to mark the end of the war with The Wall Street Journal.

On Thursday, Mr. Obama acknowledged his complicated history with military engagement in Iraq and concerns Americans may have about re-engaging there, however limited.

“I ran for this office in part to end our war in Iraq and welcome our troops home,” he said. “I will not allow the United States to be dragged into fighting another war in Iraq, so even as we support Iraqis as they take the fight to these terrorists American combat troops will not be returning to fight in Iraq.”

In every military decision Mr. Obama has faced since taking office, people in the room say the burden of proof lies heavily with officials advocating the use of force. Mr. Obama pulled back at the last minute on U.S. military strikes against Syria last summer in response to President Bashar al-Assad’s use of chemical weapons, a move he previously said would cross a “red line.”

Repercussions from that decision have rippled across the globe. U.S. allies have questioned whether the U.S. would continue to back them, and the president since has had to personally reassure leaders from Europe to the Middle East and Asia as to America’s steadfastness.

His decision Thursday—to authorize but not order strikes—fits a pattern. In Afghanistan, Mr. Obama announced a surge in 2009 that was larger than his liberal supporters wanted, but his withdrawal timetable was criticized by Republicans.

He struck a similar note when he announced plans to keep some 9,800 U.S. troops in Afghanistan after the end of the combat mission there this December, but would withdraw virtually all of them by January 2017.

Mr. Obama has tried to make his policy personal for Americans who have lived through more than a dozen years of war. “You are the first class to graduate since 9/11 who may not be sent into combat in Iraq or Afghanistan,” he told cadets at the U.S. Military Academy at West Point this summer.

That case will be harder to make after the new U.S. mission in Iraq. “Anytime you use force, you have to be able to answer the question ‘and then what?'” said Mr. Hill, the former U.S. ambassador.

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