If truth is the first casualty of war, law is apparently the last, at least for President Barack Obama.

Obama came to office declaring his determination to reimpose legal limits on the American effort to defeat al Qaeda. He swore to close Guantanamo Bay, abolish torture, tighten rules for the treatment of terrorist prisoners and rein in the broad executive power President George W. Bush had claimed in the global hunt for terrorists.

But after five-and-a-half years of near-constant terrorist brush fires in Africa, the Middle East and South Asia, and a Congress that remains largely unwilling to update key counterterrorism legislation, Obama appears finally to have surrendered to a very loose legal definition of where and when he can use military force against terrorists.

In his prime time speech Wednesday evening, Obama told Americans he was expanding attacks against the group calling itself the “Islamic State”, also known as ISIS or ISIL, by targeting its fighters not just in Iraq but also in Syria. “I will not hesitate to take action against ISIL in Syria as well as Iraq,” Obama said, “This is a core principle of my presidency: If you threaten America, you will find no safe haven.”

Strategically, that makes sense. Speaking to reporters before Obama’s speech, a senior administration official explained, “ISIL is moving with impunity back and forth from Syria to Iraq, and vice versa, each time and from each place gaining arms, gaining manpower, gaining fuel, literally and figuratively, for their fight.”

Legally, however, Obama’s authority to attack ISIS in Syria is on shaky ground. Under the Constitution, Congress decides if and when the U.S. goes to war. In 2002, it authorized President George W. Bush to attack Iraq. That authorization, broadly interpreted, can be read to include the threat ISIS now poses there. But it doesn’t apply to Syria, at least not easily. And the Obama Administration announced this summer that it was no longer using the 2002 authorization to justify its actions.

Instead, Obama claims he has authority to bomb ISIS in Syria under the Sept. 14, 2001 authorization from Congress following the 9/11 attacks. In the call with reporters, Obama’s senior administration official said, “We believe that he can rely on the 2001 AUMF [Authorization for Use of Military Force] as statutory authority for the military airstrike operations he is directing against ISIL.”

That joint resolution gave the president the power to “use all necessary and appropriate force against those nations, organizations, or persons he determines planned, authorized, committed or aided the terrorist attacks that occurred on September 11, 2001, or harbored such organizations or persons, in order to prevent any future acts of international terrorism against the United States by such nations, organizations or persons.”

A variety of legal scholars on the left and the right, including Obama himself, have argued that authorization is too broad and needs to be rewritten so it doesn’t give eternal war-fighting power to all future presidents. And as Jack Goldsmith writes for TIME today, it’s a stretch for Obama to claim it applies to ISIS, given that ISIS and al Qaeda split earlier this year.

According to a 2012 speech by Jeh Johnson, the Secretary of Homeland Security who previously served as Obama’s top lawyer at the Department of Defense, there are two characteristics that a group must have to be considered an “associated force” with al Qaeda under the 2001 authorization. First they must be “an organized, armed group that has entered the fight alongside al Qaeda,” and second, the group “is a co-belligerent with al Qaeda in hostilities against the United States or its coalition partners.” The White House has yet to release to Congress or the public any detailed analysis of their determination that the Islamic state meets these standards.

If Obama is breaking the law, don’t expect much to come of it in the short term. The consequences of Obama’s legal interpretation, beyond his own discomfort, are not likely very great. The Bush administration showed the bar for legally constraining presidential counterterrorist actions is high, and even when it is surmounted there are little or no penalties. Politically, the president has nothing to fear: no matter how angry they are about the new effort against ISIS, the left wing of Obama’s party isn’t going to impeach him, and the right won’t either, at least not for going after Islamic extremists.

In the long term, perhaps Obama’s legal legerdemain will boost those who want to come up with new, clearer legal frameworks for international counterterrorism operations. But for now Obama, like Bush before him, seems determined to act without them.

Contact us at letters@time.com.