A standard Trump negotiating tactic: threaten something awful, something he could actually do, and then, when the other party becomes reasonable, withdraw the threat. He threatened trade war with the EU and, according to today's story from the Associated Press, the EU just "blinked," gave him at least some of what he wanted.
Instead of trading something valuable to us for something valuable to them, he threatens and then stops threatening. I guess a cynic could call it his version of the "protection racket" long practiced by the mob.
I'm sure he'd describe it as somebody being abusive toward us and us threatening to return the 'favor' with interest. Whatever you call it, it works reasonably well and I hope he keeps it up.