This week marks exactly 40 years since Iranian students overran the US embassy in Tehran and took 52 people working at the embassy hostage in a siege that was to last 444 days and irrevocably shape relations between the western world and Iran, a pattern that persists to this day. The hostage crisis that began on November 4, 1979, permanently damaged Iran’s relations with the West took place less than a year after the onset of the Iranian Revolution, which saw the rise to power of Ayatollah Ruhollah Khomeini after a long exile. The students who stormed the embassy had initially wanted to stage a sit-in to demand the return of Iran’s last shah, Mohammad Reza Pahlavi, so that he could face justice. He had been ousted by the popular uprising in January 1979 and was seeking cancer treatment in the US at the time. But the move quickly escalated after Khomeini, who headed the government at the time, declared his support for the embassy takeover. Ebrahim Asgharzadeh, the 23-year-old engineering student who led the takeover, said Khomeini’s backing of the takeover caused the country to erupt in “Islamist revolutionary fervour”. As a result, civil servants working at the embassy paid the price for decades of US meddling in Iranian politics. The US had supported the shah’s regime, even helping the Iranian monarch to overthrow the country’s democratically elected government in a CIA-backed coup in 1953. For the students at the embassy, this was supposed to be the moment the Iranian people took back the fate of their country in their own hands. Instead, they unwittingly contributed to a crisis that still haunts Iranian-American relations. Asgharzadeh says he now regrets his part in a siege that only helped to alienate his country from the international community. To this day, the US has yet to reopen an embassy in Tehran while economic sanctions, imposed in the aftermath of the crisis and briefly lifted after the 2015 nuclear deal, continue to financially squeeze Iranian citizens. What is more, the hostage crisis shaped the very identity of the regime in Tehran around anti-American and anti-imperialist values, and has been vaunted as a point of national pride. The former US embassy has now become a museum chronicling US “arrogance” around the world, according to the Iranian Fars news agency. The regime in Tehran has since pursued a similar approach in its foreign relations. Since the 1979 siege, taking foreigners or dual nationals hostage has become routine practice and has even served as a strategy in Iran’s dealings with the West. Last year Aras Amiri, a young British Council worker, was detained in Evin prison – a detention facility that is notorious for housing political prisoners and foreigners, often on bogus charges. Amiri has been sentenced to 10 years in jail for “cultural infiltration through the arts”. In 2016, Nazanin Zaghari-Ratcliffe, another British-Iranian national, was sentenced to prison for “plotting to topple the Iranian government” and has been separated from her young daughter and her husband ever since. These charges are clearly trumped up and Zaghari-Ratcliffe and others in her situation are simply being used as political pawns. Meanwhile tensions have been mounting between the US and Iran since American President Donald Trump decided to withdraw from the flawed nuclear deal last year, as Washington ramped up its efforts to punish Tehran’s nefarious activities. Iran’s blackmail diplomacy has failed to achieve its aims but it has contributed to an image of a regime prepared to challenge a global superpower with whatever means available. And while the hostage crisis has been framed by the regime as a symbol of its fight against western imperialism, its 40th anniversary, which comes amid a wave of anti-Iran protests in Iraq, has highlighted the fact Tehran is replicating the very imperialist model it claims to be fighting against. For years, the Islamic Revolutionary Guard Corps’ Quds Force, a paramilitary unit responsible for Iranian operations on foreign soil, has empowered armed militias in Lebanon, Yemen and Iraq, which have challenged the authority of governments in their respective countries and terrorised civilians. This is partly what has triggered tens of thousands of Iraqis to pour onto the streets of their cities over the past few weeks. Their demands have been met with teargas and live ammunition from security forces and Iran-backed militias. But the resolve of demonstrators has been undeterred by the bloodshed, which has claimed at least 250 lives. Forty years after the US embassy siege in Tehran, dozens of Iraqi demonstrators stormed the Iranian consulate in the revered city of Karbala, lowering the Iranian flag and replacing it with the Iraqi one. In Lebanon, protesters have also taken to the streets, with people in the country’s Shiite majority south chanting slogans against the Amal movement and criticising Hezbollah – two groups that are backed by the regime in Tehran. Four decades on, Tehran’s attempts to imprint its modus operandi show no sign of waning – but they are being challenged.