What did Donald Trump do today?

He used social media to ask Iran to please stop fighting back.

Iran has now completely shut down ship traffic through the Strait of Hormuz, the chokepoint through which about a fifth of the world's oil flows. From the northern coast, it can launch missiles, drones, or even fast attack boats. 

 

The advantage Iran—a country as big and populous as the entire Eastern time zone of the United States—has if it wants to shut down the Strait is difficult to overstate. Merchant vessels in the Strait are slow, difficult to defend even with a naval escort, and utterly vulnerable to attacks that a naval vessel could withstand. As one expert put it, "some guy with an RPG" in a commercial speedboat could easily cause catastrophic damage to an oil tanker.

Iran could also mine the strait, whose navigable portion is just a few kilometers wide at one point, and there are reports today that it is already doing so. The Trump administration claims to have destroyed ten "inactive" minelaying vessels today, but almost any boat big enough to hold a mine can deploy it, and Iran has many such craft in the Strait.

Astonishingly, the Hormuz situation seems to have caught the Trump administration entirely by surprise, according to senators who attended a classified briefing on it today. In fact, the Trump administration ordered the last of its four Avenger-class minesweepers out of the Persian Gulf just weeks ago.  

That was the context today for a Trump social media post in which he asked Iran to… not do that.

If Iran has put out any mines in the Hormuz Strait, and we have no reports of them doing so, we want them removed, IMMEDIATELY! If for any reason mines were placed, and they are not removed forthwith, the Military consequences to Iran will be at a level never seen before. If, on the other hand, they remove what may have been placed, it will be a giant step in the right direction! President DONALD J. TRUMP

Trump—who declared and un-declared victory several times yesterday—was already threatening Iran with maximalist military consequences. It's not clear why he expects a government now led by a man whose family was killed by the initial attack last week to agree to act in Trump's best interests.

Why does this matter?

• A president who doesn't understand that large, well-armed, hostile countries can fight back isn't competent to lead military actions. 

• It's hard to imagine a way to make the United States look weaker than to have its president trying to win conflicts by tweet.