This is a man who’s already declared Trump’s emergency declaration “inconsistent with the U.S. Constitution” and who’s retiring from the Senate next year. He’s 78, too. He’s not headed to K Street, he’s headed to retirement. He has zero reason to refrain from joining Collins, Murkowski, and Tillis and becoming the 51st vote in the Senate to block Trump’s emergency decree. There’s nothing Trump or Trump voters in Tennessee can do to punish him.

And yet he’s holding back for now, all but begging Trump to change course so that he doesn’t have to cross the aisle and vote with Democrats on this.

If Alexander’s as worried about executive encroachment on separation of powers as he claims here, he should relish the opportunity to have this fight. Convincing Trump to back off his emergency decree will do nothing to deter a future president from issuing a decree on another matter. Whereas setting a precedent in Congress of rebuking the White House when it tries a power grab over appropriations might get the legislature thinking about guarding its prerogatives a little more jealously.

Note that he’s not asking Trump to back off on wall funding on grounds that Congress refuses to appropriate the money. He’s perfectly fine with POTUS using other executive authority to move already-appropriated funds around; what he objects to, it seems, is doing it under the rubric of a “national emergency.” Convincing Trump not to use that particular authority to pay for the wall would be a modest victory, but if the executive can reprogram funds that Congress has directed for other purposes via other authority then he’s really just taking a different route to the same destination. How serious is Alexander about separation of powers if, fundamentally, his objection is to terminology?

He’s not the only one with cold feet about voting with the Democrats:

Alexander, Paul, Gardner, Lee, Rubio, Romney, and maybe a few others are all stuck in a standoff in which whoever announces his opposition to the emergency decree next will become the decisive vote and attract the opprobrium of the base. They’re playing a little game of chicken, with no one quite yet ready to swerve. (My money’s on Gardner as the next domino to fall since he has the most to gain electorally by doing so.) These guys should all huddle up and work something out in which they declare their opposition in a joint statement so that technically none of them is the 51st vote. Which is what I assume will happen as we get closer to the floor vote and they grudgingly accept that Trump’s not going to bail them out by changing his mind on this, no matter how Alexander might plead with him to do so.