opinion
Open this photo in gallery:

U.S. President Donald Trump exits Air Force One at Joint Base Andrews, Md., after attending the World Cup final on Sunday.Jacquelyn Martin/The Associated Press

“Why is Trump risking midterm disaster by resuming the unpopular Iran war?” asked a recent headline in The Guardian.

Wrong question.

Most coverage of the renewal of hostilities rests on the mistaken assumption that this story’s protagonist must be U.S. President Donald Trump. While there’s no arguing who started the war, there’s been rather a lot of narrative evolution since then.

The strategic initiative passed some time ago from Washington to Tehran. The head of state of the most powerful nation on the planet is no longer the guy driving the action. He’s now more object than subject.

To borrow a turn of phrase from that movie where Tom Hanks’s ship gets commandeered by pirates: Iran is the captain now.

David Shribman: As a wartime president, Trump just declared war on his own government

Once Mr. Trump realized that he couldn’t achieve any of his vague war aims through military force, he tried to escape from the quagmire by paying Iran a ransom.

The memorandum of understanding agreed to last month offered Tehran an unprecedented payoff – including the lifting of a U.S. naval blockade imposed during the war, a temporary end to long-standing financial sanctions on oil sales and the unfreezing of some Iranian assets – in return for Iran agreeing to stop the war.

Notice who got paid. Notice who paid.

In the month after the U.S. Navy lifted the blockade, Iran is believed to have shipped about 70 million barrels of oil from the Persian Gulf, worth at least US$5-billion. The MOU threw Tehran a financial lifeline, in return for nothing more than restoring the pre-war status quo of free passage through international waters. The MOU also laid the groundwork for those financial rewards to continue, and for more goodies if Iran played ball on the future of its nuclear program.

The right question to ask is: “Why did Iran resume the war? What further rewards does it believe it can unlock?”

There appear to be two answers.

Tony Keller: Trump sincerely wants to wash his hands of the Iran war. But he doesn’t have the cards

First, Iran aims to extract a larger ransom. Second, it hopes to persuade the countries of the Gulf – American allies hosting American military bases – that they would be better off if they took a step back from the U.S., or if U.S. forces decamped from the region.

Ship traffic through the strait ramped up after the MOU, but much of it was using a U.S.-promoted southern route that hugged the coast of Oman, rather than a northern route Iran laid out close to its coast. Tehran appears to have decided that was undermining its leverage and its ability to charge ships protection money – sorry, I meant tolls.

In early July, Iran began warning vessels against using the southern route, and it fired at some of them. This was to prevent a return to the status quo ante of free navigation.

It left Mr. Trump with two choices: allow Iran to take control of a vital international waterway by military force, or use U.S. military force to try to stop this.

Again, notice who is acting and who is reacting. Notice who is bidding to take over new turf, and who is trying to not surrender more ground.

The first round of the war showed the Iranian regime that their military can close the strait to most traffic indefinitely, while the U.S. military does not appear to have the ability to reopen it.

U.S. announces another soldier’s death, launches more air strikes as Iran targets Gulf states

The Iranians have also demonstrated that, in addition to kneecapping their neighbours’ economies by impeding shipping, their missile and drone strikes can inflict billions of dollars of damage on ports and oil installations across the region.

On Monday, the Houthis of Yemen, an Iranian proxy with a substantial stock of ballistic missiles and drones, announced a “maritime embargo” on Saudi Arabia. This can be effected through threatening to fire on the Bab al-Mandab strait, which is used by vessels carrying Saudi oil diverted by pipeline from Persian Gulf ports to the Red Sea. (Tankers from western Saudi Arabia can also exit the Red Sea through the Suez Canal – but the largest vessels don’t fit, and it’s the wrong direction for oil destined for Asia.)

The best weapon at Washington’s disposal is probably the naval blockade of Iranian ports, which was imposed during the latter part of the first round of the war, lifted by the MOU and has now been reintroduced.

A blockade will eventually impose heavy economic pain on Iran. That could bring it back to the table, and render it willing to accept a settlement that does not include it gaining control over the Strait of Hormuz.

But the economic pain of a blockade could take months to weigh on Tehran. Right now, it’s still counting the windfall from a month of MOU-granted oil sales.

The war will end when the Iranian regime decides that it has won enough, or when in its calculation the price being paid in pursuit of its objectives is too high.

Like Mr. Trump prior to Feb. 28, there’s a danger that Iran miscalculates how far it can push Washington and its neighbours. The only thing certain is that, for the moment, the hard men of Tehran are in the captain’s chair.

Follow related authors and topics

Authors and topics you follow will be added to your personal news feed in Following.

Interact with The Globe