Donald Trump may never follow through on his threat to charge ships for protection as they pass through the Strait of Hormuz. But it’s already a gift to Tehran.Trump’s tollboothWhen Trump announced on Monday that tankers crossing the Strait of Hormuz would have to pay the United States 20 per cent of the value of their cargo, Washington’s allies were shocked. But Iran’s foreign minister, Abbas Araghchi, immediately endorsed the principle.“POTUS is absolutely right. Whoever provides secure and safe passage of commercial vessels through the Strait of Hormuz should be compensated for this service. Iran has always been the GUARDIAN of the Strait and will remain so FOREVER. 20% is of course too much. We will be fair,” he wrote on X.The US and its allies have long portrayed the contest over the strait, a transit route for 20 per cent of the world’s oil and gas before the war, as a dispute over freedom of navigation. Secretary of state Marco Rubio articulated the principle clearly during a visit to the Gulf last month.“No country is allowed to charge tolls or fees on an international waterway. That’s existing international law. That’s the way it is in international waterways all over the world, and that’s the way we expect it’ll be here,” he said.Iran has been asking shipping companies to pay a fee of up to $2 million for each vessel it allows to pass through the strait near its coastline and its forces have been attacking ships for using an alternative route along the coast of Oman. It is these attacks that triggered the US bombing of Iranian targets over the past week and Tehran’s retaliatory strikes against US assets in the Gulf states.Despite the escalating attacks, indirect negotiations between Washington and Tehran have continued, with Oman presenting a compromise proposal on the strait to Iranian negotiators in Muscat on Saturday. This would have allowed for two shipping corridors, with one along the Iranian coast requiring ships to get approval from Tehran but remaining toll-free while the other, Omani route would be open to free navigation as before the war.Iran’s negotiators returned to Tehran to consult on the proposal but Trump appears to have believed that they accepted it, claiming that they reneged on it later by attacking another ship in the strait. The US escalated its attacks on Iranian targets after that, announcing on Monday that it will reimpose its blockade on Iranian ports in the Strait of Hormuz from 9pm Irish time this evening.Trump’s proposed toll would be much higher than the $2 million Iran has been demanding, amounting to an estimated average of $32 million for each supertanker crossing the strait. And he named US Gulf allies Saudi Arabia, the United Arab Emirates, Qatar, Bahrain and Kuwait as countries he expected to pay the toll.“I want to be reimbursed because we’re protecting a very rich portion of the world, we’re spending money, and so what we’ve done is we are going to be reimbursed for protection,” he told reporters in the Oval Office.Washington’s allies in the Gulf and elsewhere are already paying a high price for the US war against Iran and after a brief interlude when shipping started to move through the Strait of Hormuz at about half its pre-war rate, it has now fallen off dramatically. The military action in the strait has already driven fuel prices upwards and Trump’s toll would increase costs further, adding to the economic pain caused by this conflict around the world.Please let me know what you think and send your comments, thoughts or suggestions for topics you would like to see covered to denis.globalbriefing@irishtimes.com