Daniel Larison of the American Conservative is one of the more outspoken critics of virtually everything Trump does with regard to other nations and foreign policy. Here's a good overview of what's gone wrong there and I'll quote this paragraph because I think it hits the target…
It's true that Trump called U.S. foreign a "complete and total disaster," and many critics of our foreign policy were pleased to hear him say that, but on reflection we can see that he was just condemning almost everything that came before him without making any distinctions. He was happy to denounce previous wars, including ones he had supported earlier, because they had turned out badly and had become unpopular. He also denounced practically every diplomatic agreement made by previous administrations with no regard for whether the agreements were working or not. According to Trump, everything that preceded him was a bad deal or the worst deal of all time.
Trump is all about what's good for the Trump brand the Trump bank account…and nothing else. And the message he thinks got him elected has been "You were dying before I came along and I'm saving you." Enough people buy that to keep him in power…so far.