In an article this week on the dangers to the UK of Islamist extremism, David Cameron suggested that Britain could work with Iran to combat the Islamic State’s offensive against Iraq. This is a dangerous and misguided proposal.

The idea that Iran and the West have mutual interests in Iraq is not new. It was suggested in the early 2000s — but lethally discredited when we discovered that the Revolutionary Guard, a central instrument of the Iranian state, together with its terrorist proxies Lebanese Hezbollah, was training, equipping and directing Shia militias to kill British and American soldiers in Iraq in their hundreds.

Likewise in Afghanistan, though on a smaller scale. Since 2006 at least, the Revolutionary Guardhas been supplying the Taliban and other insurgents with weapons and ammunition to attack British, American and Afghan targets, as well as supplying, funding and running training camps in Iran for Afghan jihadists.

Is there no contradiction, then, in a fanatically Shia Iranian regime supporting Sunni Taliban fighters? Anyone who believes that, fails to understand the cynical pragmatism of Iran’s rulers.

An active al-Qaeda network — also of course Sunni — operates today in Iran with the full knowledge and support of the regime. Led by the Syrian-born Yasin al-Suri, this network organises the movement of al-Qaeda terrorists, documentation and funding, from and through Iran to Pakistan, Afghanistan and the West. Recent terrorist plots in Europe, the United States, Canada and against Western targets in Egypt have been linked to Suri’s Iran-based cells. Links have also been identified between this al-Qaeda network in Iran and the 7/7 bombings in London as well as a planned attack against Heathrow in 2006.

Read the article in full at The Times.