White House sources are now claiming that this threat — remember, the U.S. has in fact invaded Mexico in the past, and the Mexicans have not forgotten — was a lighthearted joke. If you believe that, I have a Mexico-paid-for border wall to sell you.

The blowups with Mexico and Australia have overshadowed a more conventional war of words with Iran, which tested a missile on Sunday. This was definitely a provocation. But the White House warning that it was “putting Iran on notice” raises the question, notice of what? Given the way the administration has been alienating our allies, tighter sanctions aren’t going to happen. Are we ready for a war?

There was also a curious contrast between the response to Iran and the response to another, more serious provocation: Russia’s escalation of its proxy war in Ukraine. Senator John McCain called on the president to help Ukraine. Strangely, however, the White House said nothing at all about Russia’s actions until Nikki Haley, the United Nations ambassador, issued a condemnation late Thursday night to the Security Council. This is getting a bit obvious, isn’t it?

Oh, and one more thing: Peter Navarro, head of Mr. Trump’s new National Trade Council, accused Germany of exploiting the United States with an undervalued currency. There’s an interesting economics discussion to be had here, but government officials aren’t supposed to make that sort of accusation unless they’re prepared to fight a trade war. Are they?

I doubt it. In fact, this administration doesn’t seem prepared on any front. Mr. Trump’s confrontational phone calls, in particular, don’t sound like the working out of an economic or even political strategy — cunning schemers don’t waste time boasting about their election victories and whining about media reports on crowd sizes.

No, what we’re hearing sounds like a man who is out of his depth and out of control, who can’t even pretend to master his feelings of personal insecurity. His first two weeks in office have been utter chaos, and things just keep getting worse — perhaps because he responds to each debacle with a desperate attempt to change the subject that only leads to a fresh debacle.

America and the world can’t take much more of this. Think about it: If you had an employee behaving this way, you’d immediately remove him from any position of responsibility and strongly suggest that he seek counseling. And this guy is commander in chief of the world’s most powerful military.

Thanks, Comey.

This column has been updated to reflect news developments.