On Sunday night at half past 11 o'clock, President Trump sent a public message to Hassan Rouhani, his Iranian counterpart. It was the sort of communication you might expect these days to issue forth from the leader of the free world in the middle of the night, which is to say that it was a tweet, mostly all caps and ending with an exclamation point: To Iranian President Rouhani: NEVER, EVER THREATEN THE UNITED STATES AGAIN OR YOU WILL SUFFER CONSEQUENCES THE LIKES OF WHICH FEW THROUGHOUT HISTORY HAVE EVER SUFFERED BEFORE.