A logical next move to de-escalate UK-Iran tensions would be for each side to release the other’s tanker: yet neither Boris Johnson and Hassan Rouhani show much respect for logic.

Watching the world from Europe these last few days, it is hard to avoid the impression that rhetoric has replaced statesmanship in the conduct of international affairs.

But the award for rhetoric of the highest order should probably go to Iran’s president Hassan Rouhani. He told the world in a powerful speech, broadcast live on state television, that “war with Iran would be the mother of all wars.” He warned once again that shipping might not be safe in the Straits of Hormuz, a strategic 39 kilometre-wide waterway at the foot of the Persian Gulf through which more than one-sixth of global crude oil is shipped, as well as one-third of liquefied natural gas.

But in the same sentence, Rouhani went on to say that “peace with Iran is the mother of all peace.” His words inevitably highlight the divisions in the West on how best to approach Tehran, as undoubtedly they were part intended to do.

Tensions between the West and Iran have been rising steadily since May last year when President Trump unilaterally pulled the United States out of the Joint Comprehensive Plan of Action (JCPOA), an agreement brokered by the Obama administration which curbed the Islamic Republic’s nuclear program in return for a substantial easing of economic sanctions.

The sanctions, agreed on at the United Nations and strongly supported by the United States and the European Union, had done significant damage to Iran’s economy. By the end of President Mahmoud Armadinejad’s government in 2013, the Iranian rial had lost two-thirds of its value.

Following an Obama-Rouhani phone conversation — the first between the presidents of the United States and Iran in 30 years — the crippling sanctions were lifted in 2015. The move followed Iran’s nuclear agreement with the United States, the United Kingdom, France, Germany, China and Russia. When Trump pulled out last year, the remaining five countries stayed in, with the three European nations, known as E3, rejecting Trump’s view that the agreement had been “worthless.”

Jeremy Hunt, Britain’s former foreign secretary and challenger to Boris Johnson in the final ballot for the Conservative Party leadership was a strong supporter of E3, leading European attempts to resuscitate the nuclear deal which appeared to be collapsing after Tehran announced it would recommence uranium enrichment. After the Iranians shot down a US drone claimed to be flying over Iranian territory, Hunt persuaded former PM Theresa May to reject Trump’s call for Britain to join a US-led maritime force to protect international shipping in the Straits of Hormuz.

But the British government fell into a trap. Through the Five Eyes network it received intelligence that an Iranian oil tanker The Grace was approaching Gibraltar, a UK enclave on the southern tip of Spain, and heading for a Syrian port on the Mediterranean, in breach of sanctions. A commando task force was flown to Gibraltar, and seized control of the docked vessel during the night.

The Iranians were furious. Although the Royal Navy had HMS Montrose in the area to protect British vessels heading past the Iranian littoral, the Iranians spotted a gap. In Oman waters close to the Straits of Hormuz, a squad of Revolutionary forces boarded the Stena Impero, a British-flagged oil tanker with an international crew, ordering it to the Iranian port of Bandar Abbas. The Iranian president says he will release the Stena Impero if the United Kingdom releases The Grace.

This incident has led to much more than a deterioration in UK-Iran relations. It has driven Britain firmly into the US camp. The United Kingdom has now abandoned Mr Hunt’s policy of trying to protect UK shipping independent of the Americans, and succumbed to pressure from the Trump administration to join the proposed international convoy, to which Australia has also been asked to contribute. Once Mr Johnson became prime minister this was always going to be the likely outcome, but Hunt’s successor Dominic Raab insists the United Kingdom will still stay part of E3.

While the prime minister will have influenced this decision, a quick analysis of Britain’s naval strength indicates there was not much choice. Mr Hunt had been pushing for a European Maritime Protection Force, but there were no takers. Germany in particular believes the future to better relations with Tehran lies in a further easing of sanctions and rejects the US hardliners, including national security adviser John Bolton, whose public utterances point to more confrontation.

British defence intelligence assessments suggest Iran now has significant naval — including submarine — capability that could wreak “more than mischief” on perceived enemies. It is common knowledge that the Royal Navy’s capabilities are stretched and insufficiently prepared for conflict.

With prime minister Johnson already engaged in a game of “chicken” with the European Union over a “no-deal” Brexit, he is unlikely to have the time or inclination for brinkmanship with Tehran. A logical next move would be for the United Kingdom and Iran to de-escalate tensions by releasing each other’s tankers: but neither Johnson and Rouhani show much respect for logic.

The Iran nuclear agreement will be second only to the faltering world economy on the agenda at the G7 leaders’ summit in Biarritz, France on 24 August. Germany’s Angela Merkel and France’s Emmanuel Macron will try and coax the United States back from the brink and into some kind of settlement. The question remains whether Johnson will continue to sit on the fence or opt for the Trump/Bolton hard-line approach.

A positive sign is that Tehran needs a deal. Although Rouhani is fully engaged in this game of brinkmanship and has the support of Russian president Vladimir Putin — who lost his seat at the top table when G8 reverted to G7 — Iran’s economy is being crippled. The Islamic Republic seems prepared to weather a threatened US-Israeli airstrike and could cause significant harm to the oil trade through the Straits of Hormuz. But the show of strength comes with a high price as an increasing portion of diminishing revenues is being spent on military hardware, including anti-ballistic and cruise missiles, as well as cyber warfare, submarines and training Hamas and Hezbollah militias.

My last visit to Iran was in the final days of Shah Pahlavi when I made a film for the BBC on how young revolutionaries, many of them educated at the London School of Economics, took control of the country’s oilfields, ending his vision of an industrial complex built on Persian leadership in the region. Ayatollah Khomeini, the mullah who ousted the Shah, and his successors, have sought a different kind of regional hegemony. Although Iran is the most populated nation in West Asia and the world’s fifth-largest oil producer, its influence has waned. Iran needs Merkel and Macron to prevail in getting Trump back to the negotiating table.

Trump’s latest decision to impose personal sanctions on Iran’s resourceful foreign minister will not help. A Chatham House post has suggested that the British prime minister could take a leading role in JCPOA mediation efforts, positioning the United Kingdom as a bridge between the European Union and the United States and in the process boosting London’s post-Brexit relevance. It’s a good suggestion, but Johnson may have already decided which side he is on.

Colin Chapman is a writer, broadcaster and public speaker, who specialises in geopolitics, international economics, and global media issues. He is a former president of AIIA NSW and was appointed a fellow of the AIIA in 2017.

This article is published under a Creative Commons Licence and may be republished with attribution.