He was explicit in 2007 that Presidents don't have the authority to act unilaterally except to stop 'an actual or imminent threat'

Charles Dharapak / AP President Barack Obama walks along the West Wing colonnade of the White House in Washington on Aug. 22, 2013

In 2007, Barack Obama was asked when Presidents have the authority to launch a military strike without congressional authorization. He had a precise answer at the ready.

“The President does not have power under the Constitution to unilaterally authorize a military attack in a situation that does not involve stopping an actual or imminent threat,” Obama told the Boston Globe.

Back then, the target in question was Iran, and Obama was a first-term Senator running for President against the excesses of George W. Bush’s foreign policy. But the statement stands in stark opposition to Obama’s view now. The Obama Administration is on the cusp of intervening in a Syrian civil war that by all accounts does not pose an imminent domestic threat to the U.S. And Obama appears set to unilaterally authorize punitive strikes against Bashar Assad’s regime.

It would not be the first time Obama acted outside his own previous definition of presidential war powers. In 2011, with a bloody conflict escalating in Libya, Obama authorized the U.S. to join an international coalition that established a no-fly zone in order to stem the threat of mass slaughter. Obama argued the intervention was justified.

“The growing instability in Libya could ignite wider instability in the Middle East, with dangerous consequences to the national security interests of the United States,” he wrote in a letter to Congress. Officials pointed to the possibility of an imminent massacre of rebel forces, but no immediate threat to national security.

“In 2007, Obama was adamant that the President did not have the power to authorize an attack if there was no imminent threat to the U.S.,” PolitiFact wrote at the time. “But now he has authorized just such an action.” The fact-checking site called the reversal a “full flop.”

He isn’t the only one. As reported by NBC News, as a presidential candidate in 2007, now Vice President Joe Biden threatened to impeach President Bush if he unilaterally attacked Iran. “And I want to make it clear, I want it on the record, and I want to make it clear, if he does, as chairman of the Foreign Relations Committee and former chair of the Judiciary Committee, I will move to impeach him.”

Now Obama appears poised to solidify his new position. In the wake of an apparent chemical-weapons attack on a rebel-held neighborhood outside Damascus, his Administration is preparing to retaliate against Syrian military targets to punish Assad for crossing a U.S. “redline.” Secretary of State John Kerry called the chemical attack, which according to the nonprofit organization Doctors Without Borders killed hundreds, a “moral obscenity.” But no one in his Administration has claimed the spiraling conflict in Syria threatens U.S. security at home.

For that reason, lawmakers in both parties are urging Obama to confer with the legislative branch before acting.

“Absent an imminent threat to United States national security, the U.S. should not be engaged in military action without congressional approval,” said Senator Tim Kaine, a Virginia Democrat and an Obama ally.

If members want to put their stamp on the decision, they disagree on what it should look like. Some, like libertarian Michigan Representative Justin Amash and Virginia Representative Scott Rigell, say it is unconstitutional for Obama to intervene in Syria without a vote in Congress. House Speaker John Boehner, on the other hand, called for “meaningful consultation with members of Congress.” The vagueness of the phrase suggests Boehner isn’t eager to take a vote that could put him on the wrong side of history if the situation sours.

He wouldn’t be alone. While Congress likes to moan about having its powers usurped, it rarely uses them: the legislative branch has not issued a full declaration of war since before Obama was born. “As a general matter, of course as we consider military options, we also look at the legal and congressional implications,” says a senior Administration official.

The White House also argues that the atrocities allegedly committed by the Syrian regime met the “imminent threat” test Obama set forth in 2007. Allowing Syria to violate international standards prohibiting the use of chemical weapons would pose future threats to the U.S., White House press secretary Jay Carney argued Tuesday. “The consequences of that standard dissolving are enormous and very detrimental to the national security of the United States,” Carney said. “I believe that absolutely allowing the use of chemical weapons on a significant scale without a response would present a significant challenge — threat — to the United States national security.”

But not even Carney argued that such a threat would require the sort of speed inconsistent with obtaining congressional approval as promised by Obama.