Almost four years ago, the former foreign secretary Jack Straw went on holiday with his wife and a couple of friends to Iran, where he experienced what he calls a “forced conscription into a thriller”. Visiting the cypress of Abarkuh, a tree estimated to be up to 5,000 years old, the foursome were confronted by a group of men dressed in religiously observant black. They were members of the Basij, the thuggish volunteer offshoot of the Revolutionary Guards, and they handed Straw a leaflet explaining why he was unwelcome in their country.

The document detailed Britain’s perfidious 19th- and 20th-century track record in Iran and claimed that the recently retired Straw was a subversive agent of the British state, using his visit to sow discord. Thereafter the Basij followed the party everywhere until the Iranian police intervened. Armed and undercover, they bundled Straw and his friends into a car, as if they were being kidnapped, and whisked them away into hiding.

As Straw drily notes, to be given police protection from criminals and terrorists is one thing, but to be given police protection against other parts of the state is quite another. “I can think of no other country in the world where that occurs,” he writes.

The English Job: Understanding Iran and Why It Distrusts Britain is a response to that strange experience and the accusations made in the Basij leaflet. The book is highly readable, full of vivid history, diplomatic anecdotes and personal observation. It explains the peculiar circumstances of a country finely balanced between becoming a nuclear power and risking international isolation. It’s written in a manner that is balanced, dispassionate and yet sympathetic to the Iranian people.

As Straw shows, Iran is a nation that remains anachronistically fixated on the UK, as if it were a superpower capable of extraordinary influence far beyond its shores. There is a reason for this. Britain did once fit that description, and there were few countries in which its long and clandestine reach was felt with more resentment than in Iran.

In the 19th century, the Iranian shah Naser al-Din granted Britain what Straw calls “the most extraordinary and rapacious business concessions”. He did this partly to recruit the British empire as a buffer against Russian encroachment, and partly for personal gain, but its effect was to establish the suspicion that the British had “only malign intentions” for Iran. That suspicion grew steadily and was confirmed in 1953 with Britain’s grubby role, along with the US, in unseating the democratically elected Iranian prime minister Mohammad Mosaddegh in an orchestrated coup. Power then swung to the shah Mohammad Reza Pahlavi, who became increasingly autocratic. Hated by many of his people, he was eventually forced to flee in the 1979 revolution.

Straw, who in 2001 became the first senior British minister to visit Iran since the 1979 revolution, is clear-eyed about, and damning of, Britain’s part in empowering the shah. But he’s not about to fall for the flagrant historical revisionism practised by the religious authorities who have held control since Ayatollah Khomeini hijacked the revolution.

“The myth in the Islamic republic today,” writes Straw, “is that the clerics stood foursquare with Mosaddegh. They did the opposite. Their overriding concern, then as now, was to preserve their power and influence within Iran.”

Former British foreign secretary Jack Straw greets Mohammad Khatami, whose eight-year tenure as president of Iran ended in 2005, in Tehran in 2001. Photograph: Reuters

That determination has led to a modern nation with enormous potential being strangled by a shadow clerical state that thwarts all attempts at political modernisation. There is, in effect, a two-state system. One is the elected politicians with their ministries and the appearance of a functioning democracy. The other, more powerful, is run by the supreme leader Ayatollah Ali Khamenei and ensures democracy is largely cosmetic.

There have been several reform-minded presidents who have sought to create a more representative politics at home and a less aggressive image abroad. They have all had to work under the watchful eye of Khamenei, and it has seldom gone well for them. And, should popular resistance grow, Khamenei is not afraid to fix elections, as he almost certainly did in 2009, triggering the Green movement protests.

Straw makes the case that Mohammad Khatami, Iran’s president when Straw became foreign minister in 2001, was someone the west could have done business with. He was beginning to push through reforms and, post-9/11, there were signs of international collaboration with the US. But that opportunity was destroyed by the inclusion of Iran in President George W Bush’s infamous axis of evil list. No one, it seems, is sure how the phrase “axis of evil” made it into the final speech. Its original author put it in with the expectation it would be taken out.

Similarly, Straw thinks Donald Trump’s withdrawal from the joint comprehensive plan of action (JCPOA) nuclear deal with Iran is another, though more wilful, mistake. Yet it has to be said that the Iranian leadership, under Khamenei, do little to encourage confidence in their actions. They have been playing a game of brinkmanship for many decades that stems in part from fear of foreign meddling but also anxiety about domestic change.

It is this tension that goes to the heart of a nation divided between public pretence and private interests. In 2011, members of the Basij – the group who tried to intimidate Straw on his Iran trip – ransacked compounds belonging to the British embassy. They smashed almost everything they could, except for one thing: bottles of alcohol, which they stole.

Like the nuclear material that Iran is currently processing, that kind of hypocrisy has a dangerous half-life. Perhaps all that’s preventing a popular uprising is the nationalism fuelled by American hostility.

This review is from the Observer

• The English Job: Understanding Iran and Why It Distrusts Britain by Jack Straw is published by Biteback (£20). To order a copy go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £15, online orders only. Phone orders min p&p of £1.99