09/11/2014 12:38 pm ET Updated Sep 11, 2014

WATCH: John McCain Explained Last Year Why The 9/11 War Declaration Doesn't Apply Now

WASHINGTON -- Late last spring, in a remarkable hearing on the authority granted to the president after Sept. 11 to go after Al Qaeda and its backers, Sen. John McCain (R-Ariz.) made a powerful argument explaining why that authority had been stretched to the breaking point by 2013, even before the current rise of the Islamic State.

McCain, a hawk on counterterrorism issues who wants President Barack Obama to act aggressively in Syria, read from the 2001 Authorization to Use Military Force that President George W. Bush signed on Sept. 18, 2001, noting that it didn't say anything about groups that did not exist at the time.

The resolution specifically targets "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."

McCain pointed out that the authorization had been expanded to target groups associated or affiliated with Al Qaeda, and pointedly asked four top intelligence and military officials why the AUMF shouldn't be updated, and how they could justify using it in so many ways that had not been envisioned directly after the terrorist attacks of Sept. 11.

Deputy Secretary of Defense Michael Sheehan's short-hand answer was that the 2001 AUMF was working, and he told the Senate Armed Services Committee, "If it ain't broke, don't fix it."

Nevertheless, McCain's concern was echoed by Sens. Tim Kaine (D-Va.) and Angus King (I-Maine), who expressed alarm at the administration's continued use of the old authorization. Kaine, noting that one official thought strikes in Syria would be permitted under the AUMF, went so far as to declare, "I just don't want to walk out of this room with any doubt that at least this senator would expect under the Constitution that an administration would come back to Congress, have that discussion and not use this AUMF to justify commencement of hostilities in that theater [Syria] or others."

But the administration disagreed then, and is using that authority now for expanding airstrikes against the Islamic State.

Watch McCain, King and Kaine above.

Michael McAuliff covers Congress and politics for The Huffington Post. Talk to him on Facebook.



John McCain