What did Donald Trump do today?

He told Americans exactly why gas prices are going to go up again.

Yesterday, Trump seized on a tweet by Canadian oil and gas industry analyst Rory Johnston. It showed a map plot of empty oil tankers rerouting in a continuous line stretching halfway around the world, bound for American oil export terminals on the Gulf of Mexico. This is, obviously, the result of a fifth of the world's oil supply being shut off by Iran's ongoing blockade of the Strait of Hormuz.

 

Johnston said it was "very cool" to see this, referring to the unusual redeployment of a substantial portion of the world's oil fleet. But Trump apparently misunderstood Johnston's enthusiasm and assumed it was a good thing for United States, and stole Johnston's map for a post to his own boutique social media account. (Johnston took the theft in good humor.)

Today, Trump doubled down on the idea that chaos in the oil markets was a positive development:

Massive numbers of completely empty oil tankers, some of the largest anywhere in the World, are heading, right now, to the United States to load up with the best and "sweetest" oil (and gas!) anywhere in the World. We have more oil than the next two largest oil economies combined - and higher quality. We are waiting for you. Quick turnaround! President DJT 

In reality, what this means is that American consumers will be bidding directly against the rest of the world for oil that otherwise would have mostly remained in the United States.

The oil market is global and complex. Refineries are built to process specific kinds of oil based on specific levels of demand in different places, and they have fixed capacities. Inefficiencies, like having to reroute a tanker fleet 10,000 miles, drive up the price. So does limited supply.

It's true that American oil company profits will go up, although Iran itself and Russia are the real winners, as both are now free from American sanctions on their oil, and both are heavily dependent on petroleum revenue to support their wars against the United States and its ally Ukraine.

But actual Americans pay more for everything when fuel prices soar like they have since the start of Trump's attacks on Iran: more for gasoline, which is now over $5/gallon on the west coast, and more for everything shipped on planes or trucks.

Why does this matter?

• A president who can't understand the most basic economic concepts like supply and demand isn't fit to hold office. 

• There's a difference between what's good for a few oil companies and what's good for 340 million Americans.