President Trump asserted on Thursday that he had no plans to commit ground forces to the U.S.-Israeli war in Iran, even though he has acknowledged he is contemplating moves that could drag the military into land combat operations. Mr. Trump’s comments still left some room for him to reverse course. “I’m not putting troops anywhere,″ Mr. Trump told a reporter who asked about using ground troops. “If I were, I certainly wouldn’t tell you.” The president has spent several days alternating between threats to escalate strikes on Iran — which at times he has insisted are an “operation” or an...