Iran’s leaders are betting the global economy will buckle before the regime does

In five tumultuous months, Iran’s surviving leaders have withstood more than 23,000 American and Israeli air strikes. Donald Trump’s decision to rain yet more high explosives down from the skies is unlikely to break their will. What matters far more is the imminent return of the US naval blockade of Iranian ports.

With that move, Trump is seeking to enforce the simple principle that Iran can only send its own ships through the Strait of Hormuz if every other country is free to do the same. If Iran starts firing missiles at passing tankers – as happened twice on Monday – then the US will ensure that the Islamic Republic cannot use this vital waterway either.

Once all of Iran’s ports are closed, the regime will lose the oil exports that provide its single greatest source of revenue. Hence, the significance of the US Central Command announcement that it will “enforce” a “blockade against vessels transiting to or from Iranian ports and coastal areas”.

Throughout the 40-day air campaign that the US and Israel jointly waged against Iran from Feb 28 until April 8, the Islamic Republic managed to close the Strait to every other country while still allowing safe passage for its own ships.

In those six weeks, tankers carrying about 1.8 million barrels of Iranian oil left the country’s ports every day and travelled safely through the Strait, usually bound for China. Even better from the regime’s perspective was that Iran’s oil exports at the height of the war often exceeded its daily peacetime average of 1.7 million barrels last year.

One of Trump’s greatest follies was to have started his campaign without having deployed enough US warships in the Middle East either to escort friendly vessels safely through the Strait or enforce a counter-blockade of Iran. Only on April 13, five days after the first ceasefire, did Trump halt the flow of tankers laden with Iranian oil and grip the throat of the country’s economy.

With that move, the US president gained a powerful bargaining chip. Yet he threw it away on June 18 by unconditionally lifting the blockade in accordance with Point 4 of his memorandum of understanding with Iran.

Now the blockade is about to return, and the US Navy will, from Tuesday night, once again prevent Iran from being able to export any oil by sea. At a stroke, the regime will face the risk of financial suffocation.

Trump will doubtless hope that this stranglehold will bring his enemies to their senses and force them to relax their grip on the Strait.

But the US president will now encounter two problems of his own making. The first is that Point 5 of his agreement with Iran states that the Islamic Republic will “define the future administration and maritime services in the Strait of Hormuz”, in “dialogue” with other countries.

Put simply, Trump has already conceded the principle that Iran has a right to “define” how ships might use this waterway, in consultation with its maritime neighbours. Before the war, by contrast, Iran had no such right, and vessels were free to pass without seeking anyone’s permission.

The second problem is that the global economy is critically dependent on the Strait of Hormuz for supplies of oil, gas and fertiliser. Iran’s leaders might calculate that they can endure Trump’s blockade – and the loss of their own oil exports – for longer than the world economy can withstand the closure of the Strait.

They will be hoping that any renewed turmoil on the energy markets might force Trump to retreat. Just as the US can strangle Iran, so Iran can choke the global economy. And the regime will believe it can hold out and suffer pain for longer.

All of Trump’s latest moves betray how he is struggling with the new reality that he has unwittingly created. His war has made Iran structurally stronger because the regime now possesses a proven ability to close the Strait and attack shipping at will.

Trump’s only hope is that his foes will buckle under the pressure of his counter-blockade. But experience suggests that the world economy might buckle first.

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