Via National Review, senators-elect Thom Tillis (R-NC) and Gary Peters (D-MI) are calling for a new Authorization for the Use of Military Force (AUMF) against the Islamic State.

This strikes me as an eminently sensible and sage proposal. Even if there’s no legal need for a new AUMF — as our actions are already sanctioned through a combination of the president’s inherent authority as commander-in-chief and Congress’s previous (and still active) AUMFs regarding Iraq and against al-Qaeda — there are other, equally-important reasons to favor Congressional approval.

Our main problem regarding the Islamic State is that nobody knows what the hell we’re doing. Despite the presidents’ claim in his September address that our objectives are to “degrade and ultimately destroy” the Islamic State, it’s neither entirely clear whether the president believes this to be true, let alone whether the American people are or should be interested in pursuing that particular task.

In a republic with a constitution like ours, the best and simplest way of testing that is to put the matter up for a vote in Congress; our representatives, being self-interested, will consult both their own judgement and the desires of their constituents. If a new AUMF passes — as I imagine it would, in some form — the American people can either reward or punish their representatives as appropriate in 2016.

Moreover, such an authorization would greatly help us prosecute the war. As things currently stand, America’s commitment to the war is based on one speech and a number of comments by the President. But in just over two years, Obama — thank goodness — will be gone. Given that these conflicts always last longer than anticipated, that our strategy is premised on allied cooperation, and that the United States already has a problem with keeping its promises in the region , it’s absolutely vital that the World knows that the United States’ commitment goes beyond the word of one man who will soon be out of office and will never again be up for election.

If telling our allies that “Don’t worry; Congress passed a resolution” sounds like a weak commitment, consider that we can’t even offer that as of now.