Europeans have a point that Mr. Trump didn’t consult them before he began this round of bombing with Israel. He’s also been high-handed with Europe over Greenland, and with the world on his unilateral tariffs. A more conventional U.S. President would have done more to cultivate personal ties with leaders who could help smooth over rough political moments. Mr. Trump always prefers the U.S. power flex, which is no doubt grating on European sensibilities.