In the Islamic Republic of Iran, Peter Calder finds almost everything is forbidden, yet accessible.

In Iran, entering a roundabout is an undertaking of knuckle-whitening implausibility. The rule, if you can call it that, seems to be that the traffic already on the roundabout gives way to traffic entering it. More likely, no one and everyone gives way all at the same time. Somehow it seems to work.

As a passenger in a range of stop-start vehicles during a month I spent in the country in September, I found the driving an apt metaphor for the way the place runs. There are rules, and some – speed limits and seat-belt requirements – are even observed, but most things seem to happen in spite of them.

Macro alias: ModuleRenderer

“In Tehran, everything is forbidden,” Ahmad told me. “And everything that is forbidden you can get.”

Ahmad was one of several young men I met who were happy to play guide for a few hours in exchange for my correcting their English. His name is not really Ahmad – you can’t be too careful in protecting those who talk to you – but the story he told was a familiar one. Iran – correctly the Islamic Republic of Iran – is a hypermoralist theocracy in which pornography, prostitution, alcohol, drugs, YouTube, Facebook, and much else besides, is banned, on pain of imprisonment, and corporal or even capital punishment. Yet the population accesses all of them with a quietly exuberant abandon. Defiance, indeed, is the currency of daily life.

Since the revolution (which marks its 40th anniversary in February) that deposed the last Shah, Mohammad Reza Pahlavi, the country has been under the control of two “supreme leaders” in succession: Sayyid Ali Hosseini Khamenei followed Ayatollah Ruhollah Khomeini, who returned from exile in Paris in 1979 to establish the Islamic Republic. There is a president and a legislature, both nominally elected, but nothing, including the presidential and ministerial appointments, occurs without the Supreme Leader’s say-so. As the PBS show Frontline reported, Iran is the only state in which the executive branch does not control the armed forces.

And the day-to-day experience of Iranians makes it plain that the ideologues who run the country prize social control based on the principles of Shia Islam ahead of economic prosperity. In particular, and despite some progress in the past decade, women are disproportionately oppressed, and labour under great disadvantage in regard to access to education, employment and the remedies of civil law. The hijab – a head-covering scarf – remains obligatory, even for tourist women.

Meanwhile, the basij, a volunteer auxiliary corps of young men recognisable by their neatly trimmed beards and black clothing, enforce internal security, police morals (they question couples walking together to establish the legitimacy of their relationship) and suppress dissidents and protest gatherings.