The Bloomberg editors make the case against Bob Corker’s Iran bill:

What’s wrong with that? First of all, by suspending the president’s power to waive existing Iran sanctions for 60 days, the bill undermines any offers of sanctions relief that his negotiators made to Iran in Geneva. And if Congress votes down the agreement, it also removes the president’s ability to renew previous sanctions waivers agreed to in November 2013. In other words, a “no” vote on a new agreement also effectively blows up the existing deal, under which Iran’s nuclear program has been frozen (and in some cases rolled back) and subject to greater inspection.

Of course, blowing up the deal is the goal of the exercise. That is why the legislation is being proposed, and that is why the opponents of diplomacy with Iran are prepared to vote for it. That is why the Republican leadership was eager to vote for it before the negotiations were concluded, but fortunately they ran into strong Democratic resistance that won’t permit a vote at least until after this month. No matter how one wants to spin it, any politician in favor of Corker’s bill is aligning himself with the forces that want diplomacy with Iran to fail.

The Corker legislation represents misguided Congressional interference in the president’s conduct of diplomacy on an important issue. Whenever presidents arbitrarily order military action without Congressional approval, we see none of the same eagerness in Congress to exercise its proper role regarding war powers. Instead we hear that there shouldn’t be “535 commanders-in-chief.” But when there are sensitive negotiations that Congress can try to derail with unwarranted and inappropriate meddling, it seems that wild horses can’t keep them from butting in to undermine U.S. diplomacy. Between the debate over the different Iran bills and the farcical AUMF process, we are witnessing the worst of both worlds in Congress: the members neglect their real responsibilities on matters of war while trying to micromanage the executive in matters of diplomacy. The Corker bill reinforces these screwed-up priorities. It should be voted down, and failing that it should be vetoed.