The important point here is that Trump caved. This is different from the issue of branding China a currency manipulator. That was a flip-flop. (He does that a lot). There wasn't a negotiation. There wasn't an exchange of demands. He just said he was going to do a thing, and didn't. The border wall funding issue was a demand in a negotiation. He demanded money for a border wall, then admitted he wouldn't veto a spending bill without the money. That's a cave. Not the same. The latter is far more dangerous to his credibility, and it brings me back to an issue that I addressed last summer in the "Political science & craziness" series.
Trump cares primarily about perceptions of strength, and so is committed to carrying out threats to his own detriment. That should give his threats more credibility than a sane actor, and give him some bargaining leverage, if played right. The border wall funding issue, though, brings us to the issue I addressed in Part V of the series-- what happens when you demand something that another actor simply cannot provide. The funding that Trump was demanding here was a nonstarter, but shutting down the government in his first 100 days would be dumb even by Trumpian standards. Would Trump be smart enough to back away?
I didn't know if he would be. He was. Give Trump credit here for recognizing when he needed to cave. There was no way this spending bill would get through the Senate in particular with that border wall funding, and Trump couldn't handle a shutdown. He was going to lose. Caving must have killed him, given how much he hates looking weak. And he looks very very very weak.
Why?
Because he is weak. He is just smart enough to recognize that he doesn't hold the cards right now. This is an unfulfillable campaign promise coming back to bite him. For those scared that Trump will do something truly, irrationally stupid, though (like me), this is actually a sign that someone is pushing him to do the smart thing.