Senate Majority Leader Mitch McConnell (center), joined at right by Majority Whip John Cornyn.AP Photo/J. Scott Applewhite

Senate Majority Leader Mitch McConnell offered members a snow-weekend surprise late Wednesday night: Quietly teeing up a potential debate on the legal underpinning for the fight against ISIS.

After months of worrying that such a resolution—known as an authorization for the use of military force—would tie the next president’s hands, McConnell’s move to fast-track the measure surprised even his top deputy, Senate Majority Whip John Cornyn, who was unaware that McConnell had set up the authorization.

“He did?” Cornyn asked National Journal on Thursday morning.

The AUMF put forward by McConnell would not restrict the president’s use of ground troops, nor have any limits related to time or geography. Nor would it touch on the issue of what to do with the 2001 AUMF, which the Obama administration has used to attack ISIS despite that authorization’s instructions to use force against those who planned the 9/11 terrorist attacks. By contrast, the legal authority put forward by the administration last February wouldn’t authorize “enduring offensive ground combat operations” and would have ended three years after enactment, unless reauthorized.

After sitting on the president’s proposed AUMF for nearly a year, amid deep infighting in the Senate over the measure, McConnell’s move came as a surprise to many members. Just in December, McConnell dismissed the idea of bringing up a new authorization, telling reporters: “It’s clear the pres­id­ent does not have a strategy in place, so it would be hard to fig­ure out how to au­thor­ize a non-strategy.”

Don Stewart, McConnell’s spokesman, said Thursday in an email that the new AUMF “is not the one the [p]resident asked for” and “not one that would tie the [p]resident’s hands.”

Stewart added that the process McConnell used to set up the AUMF, known as “Rule XIV,” merely sets up the authorization for a future vote, but does not put it on the calendar—meaning a vote could come at any time, or not at all. The resolution already has four Republican cosponsors: Sens. Lindsey Graham, Daniel Coats, Joni Ernst, and Orrin Hatch.

That came as news to many members Thursday. Several senators said they were unaware that McConnell had moved to fast-track an authorization and some Republicans immediately pointed out issues with the proposal. Sen. Jeff Flake, who introduced a more limited AUMF with Virginia Democrat Tim Kaine last June, said: “We need to pass one—we don’t need to just make a political statement.”

“I just know that it’ll be difficult to get Democratic support on this,” he added.

Senate Foreign Relations Chairman Bob Corker said that there is still a “wide diversity” of opinions on the issue. Some Democrats were critical of even the president’s own draft AUMF, warning that they’d need additional restrictions from the administration on troop levels and geographic boundaries before they could support any authorization. Republicans, meanwhile, worried deeply about restricting the president as this administration, and the next one, work to combat ISIS.

Corker’s committee—and the Senate at large—was so deeply divided over the president’s AUMF proposal in February that the panel ultimately dropped the issue, with Corker arguing with the administration that no new authorization was needed. “I don’t think it changes anything,” he said, of the new resolution.

“I’m in the same place that I’ve been—and that is I believe the administration has the authority to do what they’re doing,” he added. “They believe they have the authority to do what they’re doing. If a consensus develops and I believe that something constructive relative to us dealing with ISIS might come out of it then certainly I’d be glad to consider it.”

In a statement from his office, Corker later added: "Senator McConnell and I have been in constant communication over this issue and there is no daylight between us on what would be needed to actually take up and pass an AUMF.”

Still, several long-time advocates for passing a new measure authorizing the administration’s war against ISIS were pleased to see an AUMF moving, however slightly, forward.

“This is the right thing,” said Graham, a cosponsor on the new AUMF resolution. “This is the right infrastructure to have.”

“If our Democratic friends don’t want to give this president and other presidents the ability to go after ISIS without limitation to geography, time and means—be on the record,” he added.

Kaine, a Democrat who has aggressively advocated for an AUMF, was thrilled Thursday that the Senate could soon take up debate, though he added that he hasn’t yet seen the details. “After 18 months, I feel like the institution might be finally waking up that this is a threat,” Kaine said. “So we’ll see what the plan is on it, but the notion that we may be finally taking our job seriously on it is something I’m hopeful about.”

Kaine said that although he and the vast majority of Congress support combatting ISIS, he disagrees with the administration that the president is within his authority to do so. “I believe the war is illegal,” Kaine said Thursday. “I don’t think there’s a legal justification for it. And I think the greatest danger we end up doing is allowing the president to wage a war without Congress weighing in.”

Kaine added that the president acted initially “to protect American lives” and credited the White House for sending over an AUMF last year. “We haven’t done anything. So just the notion that maybe finally there’s some interest in this, I find gratifying. But we’ll have to work through the details,” he said.

Several Democrats said they were unaware of or hadn’t read the new AUMF language, but some greeted the opportunity to open debate on the issue.

“I haven’t read it but I’m encouraged by the fact that he’s not running away from this issue any longer,” Senate Minority Whip Dick Durbin said of McConnell. “The president has asked for this for a long time.”

Sen. Robert Menendez, who helped to get a Democratic draft AUMF through the Foreign Relations Committee as chairman in December 2014, said that the new authorization was news to him, but that he supported bringing up the issue.

“I’m for the Congress voting on an AUMF; of course it depends what the AUMF looks like,” Menendez said Thursday. “I don’t want a blank check,” he said.

Cornyn, who in December said that Republicans would not present an AUMF of their own until the president outlined a strategy, said that he nonetheless welcomed debate on the issue.

“I don’t think we should be afraid of that debate, but we need a coherent strategy from the president which we still don’t have and we also don’t need to tie the hands of the next president by restricting what the president can do,” Cornyn said.

“What I find kind of ironic about this is the president apparently thinks he has all the authority he needs to do what he’s doing,” he added. “But I’m not afraid of the debate, I think it’s an important debate to have, and certainly the people we send in harm’s way need to know that the country is behind them. So, thanks for telling me.”

This article has been updated to clarify that McConnell's move sets up a possible floor debate, but does not guarantee one.

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