Prime Minister Benjamin Netanyahu of Israel has bombed Iran in what may lead to yet another war in the Middle East, and the challenge for President Trump will be to protect American troops in the region and to stay out of this mess.

Netanyahu justified his latest military campaign by saying that Iran was a “clear and present danger.” And it’s true that Iran was enriching uranium to worrisome levels. It’s believed to be just weeks from having enough fissile material to make several bombs (although creating bombs and a way to deliver them would take much longer).

But a key reason for Iran’s increasingly dangerous course was the past colossal misjudgments by Netanyahu and Trump in their dealings with Iran. With strong backing from Netanyahu, Trump in 2018 pulled out of the nuclear agreement that President Barack Obama had reached that largely contained Iran’s nuclear program.

Trump apparently expected Iran to come crawling back and make concessions. Instead, Iran accelerated its enrichment of uranium. One former Israeli security official has described the decision to cancel the deal in 2018 as a “disaster,” and another has said it was a “historic mistake.”

Netanyahu’s bellicosity didn’t work then, and it seems unlikely to work now. The bombing might have been intended to undercut Trump’s recent diplomatic efforts to restore something close to the original nuclear deal with Iran.

We’ll see what the results of the bombing are, but there have always been doubts that the Iranian nuclear site Fordow could be destroyed, at least without American bunker-buster bombs, because it is deep underground. (It was unclear as of late Thursday whether it had been targeted.) Israel has also reportedly bombed housing where Iranian nuclear scientists live, and that may be more effective; military experts have said for years that Iran would have a harder time replacing its nuclear scientists than its centrifuges.