With no signs of action on the Yemen War Powers Act challenge in the first couple of days this week, Wednesday is looking to be the start of the effort in earnest. Sen. Bernie Sanders (I-VT) has confirmed he will be pushing the “motion to proceed,” which will start the floor debate, and ultimately the vote on the bill itself.

The bill would mandate the US to end its involvement in the Saudi-led war in Yemen, which was never authorized by Congress. Last week, the Senate voted in favor of allowing a full floor debate and vote on the matter.

The bill is widely expected to pass, with many in the Senate angry at the Saudis for the murder of Jamal Khashoggi. Reportedly, the House Republican Rules Committee is set to vote on a rules question surrounding War Powers challenges on Wednesday as well, which may open the possibility of a House version of this bill getting a hearing after months of effort by the leadership to prevent that.

Despite that, this is a substantial accomplishment for the Senate, as one of very few times in recent history that Congress has not only asserted a theoretical ability to legally challenge a plainly unauthorized US war, but has actually brought the challenge up to the floor for a vote.

Given how many unauthorized wars the US finds itself in these days, an expectation that Congress will, or at least might, challenge some of them could be a game changer for US foreign policy. It is unsurprising, then, how the administration is pushing against this vote.

Those wishing to call their senators should do so very soon before the matter comes up for vote. You can do this by calling the Capitol switchboard at (202)224-3121 or by finding individual contact information here.