Bangladesh, March 14 -- By any reasonable measure, the past two weeks have not gone according to plan in Washington or Tel Aviv. When Donald Trump remarked in a recent interview that regime change in Iran “is not going to happen easily,” the statement carried the weary tone of a man acknowledging political gravity. It was less a revelation than a quiet admission of failure.

For weeks, the strategy had seemed straightforward: military pressure, psychological warfare, and the familiar expectation that domestic unrest would fracture the Iranian state from within. Israel joined in military operations. Commentators in Western capitals predicted a predictable script—bombs from outside, protests from inside, and eventually the...