What did Donald Trump do today?

He casually threatened to "blow up" Oman, a military ally and diplomatic partner in his war on Iran.

It's been 89 days since Iran functionally closed the Persian Gulf to all but a few ships per day, drastically affecting the world economy and forcing the United States to sue for peace with a nation that Trump has repeatedly claimed was already defeated.

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It's not in Iran's best interests to keep the Persian Gulf closed forever, but it is to Iran's advantage to maintain active control over the formerly open passage. It is doing this now by threat of force, because cargo and tanker ships are slow and vulnerable, but legal control recognized by some international agreement would be better for Iran, not least because this would create a mechanism for it to charge tolls.

Accordingly, its counter-offers at the negotiating table have made a priority of recognizing its de facto ability to cripple world trade (and its willingness to do so). But to give the appearance of regional unity, those proposals have generally offered to split the proceeds with the nation of Oman, which sits on the other side of the entrance to the Strait of Hormuz.

 

Oman, which has maintained some backchannel diplomatic relationships with Iran, has played a key role in negotiations, which may explain why Iran's government has offered them that olive branch.

Today, at a Cabinet meeting where he once again had difficulty staying awake, Trump was asked about the possibility of joint Omani-Iranian oversight of the Strait. Trump, whose company is "developing" a luxury resort hotel in the capital Muscat largely paid for by the Omani and Saudi governments, responded that if Oman tried to enter into any such arrangement, "we'd have to blow them up."

Oman is a military ally of the United States, and has been attacked directly because of the war. Nineteen of its citizens have died in those attacks.

This is at least the fifteenth country that Trump has threatened to launch military attacks against. Many of them, like Panama, Canada, Ukraine, Denmark, Mexico, and now Oman, are military and diplomatic allies.

Why does this matter?

• No matter how many times Donald Trump does it, threatening or attacking the United States' allies is an evil act that makes the United States less secure. 

• A president who can't remember or doesn't care who is on which side of a war he's fighting is unfit for command.   

• If Trump were in a position to dictate terms about how the Strait of Hormuz is reopened, it would already be open. 

• Constantly making empty threats shows weakness, not strength.