Earlier this summer, Virginia Senator Tim Kaine found himself in the Grand Foyer of the White House playing the foreign policy–hypothetical game with President Obama. Over drinks with some Senate Democrats, the President mentioned Kaine’s article that day in the Washington Post demanding a congressional vote to authorize any new military action against the Islamic State of Iraq and Greater Syria (ISIS), the armed extremist group overtaking large chunks of Iraq.
The Law Professor in Chief, who campaigned for office promising to rein in executive power, proposed some scenarios. “He’d say, ‘Here’s the situation. Do you think I have executive authority to act?'” Among the possibilities Kaine recalls: What if there is an imminent threat to a U.S. embassy? “We generally agreed on most of them,” says Kaine. But not all.
Two months later, those debates are no longer hypothetical. Since Aug. 8, Obama has unilaterally ordered more than 100 bombing runs on ISIS targets in northern Iraq, citing his authority under Article II of the Constitution to protect U.S. lives and offer humanitarian aid. Hundreds of military advisers have been dispatched to Iraq, along with shipments of lethal equipment to proxy forces in the region. Through it all, the White House has maintained that Obama has no plans to seek permission from Congress, which returns from recess on Sept. 8.
The Constitution gives the President the power to defend the country as Commander in Chief, but it delegates the power to declare war to Congress. Kaine is one of several Senators who believe Obama has stretched his powers about as far as they can go. “I am worried about the consequences of Congress basically saying the President can decide unilaterally which organizations to launch air strikes against,” says Kaine.
The Obama Administration, meanwhile, has been signaling that the conflict with ISIS is likely to expand before it contracts. U.S. officials worry about what they believe are hundreds of ISIS fighters with Western passports who could attack Europe or the U.S. if they return to their homelands. General Martin Dempsey, who chairs the Joint Chiefs of Staff, told reporters that defeating ISIS will require action by U.S. or other forces on both sides of the Iraq-Syria border. Days later, Pentagon sources leaked news of new U.S. surveillance flights over Syria to better map out ISIS positions, a possible prerequisite to expanded bombing efforts. “Rooting out a cancer like [ISIS] won’t be easy and it won’t be quick,” Obama said on Aug. 26. Though the White House insists no decisions have been made for an expanded campaign against ISIS, no one denies that preparations are under way.
The ironies of the situation are striking. A President who helped build his national profile by opposing the war in Iraq now must decide whether to force a vote on a similar military adventure just weeks before midterm elections. But the commander who deferred to Congress rather than launch air strikes on Syria last year may not be able to attract the votes on Capitol Hill that he has in the past claimed to need. “I believe our democracy is stronger when the President acts with the support of Congress,” Obama said one year ago. “And I believe America acts more effectively abroad when we stand together.”
There are plenty of reasons for the White House to avoid a bitter debate over a new war in the Middle East. Obama’s attempts to get approval from Congress for the last round of Syria strikes failed to muster the required votes, and it divided his own party, upsetting many on the left. He has also spent some of his second term celebrating what he described as the coming end to the war on terror, a goal that seems increasingly distant. Congressional leadership on both sides is skittish about a vote. “Neither he nor the Congress wants to have this dance now,” says Jack Goldsmith, who led the Office of Legal Counsel for President George W. Bush. “That’s really what is going on.”
In the meantime, the White House has been searching for a legal justification for a protracted military campaign that doesn’t involve going to Congress. A 2002 congressional authorization to use force in Iraq remains on the books, but the White House announced in July that the document “is no longer used” and should be repealed. That leaves the 2001 congressional authorization to pursue those responsible for the Sept. 11 attacks, which a White House spokesperson says the Administration is “currently reviewing” to see if it applies to ISIS.
But Obama allies like Kaine, who otherwise supports Obama’s ISIS campaign, say that document clearly doesn’t cover ISIS, which did not exist in 2001. Far from being a partner of al-Qaeda, ISIS has emerged as a rival in the region. And in 2001, Congress rejected a White House request for broader authorization to allow military force against threats unconnected to al-Qaeda.
A third option–perhaps the most likely outcome–is for Obama to declare that his constitutional powers allow him to continue the conflict without Congress. A Vietnam-era law requires the President to seek congressional authorization for hostilities within 60 days of their launch, or begin military drawdowns; that deadline would expire after Oct. 7. But Obama never sought such authorization for the bombing campaign that toppled Libyan strongman Muammar Gaddafi in 2011. Instead, his lawyers argued that the limited nature of U.S. support for air strikes on Libya did not amount to “hostilities” under the law.
In the end, the greatest risk for Obama in avoiding Congress may be to his legacy. No court is likely to force him to stop military action, and Congress is unlikely to unite around a demand for a vote. But Obama has repeatedly promised the American people a more democratic approach to warfare. As so often happens in the Oval Office, the President must now decide whether to pay a political price to uphold his public vows.
–WITH REPORTING BY JAY NEWTON-SMALL AND ZEKE MILLER/WASHINGTON
This appears in the September 08, 2014 issue of TIME.