Here's a flavour of his argument: "Far from merging with local communities, many seem to have decided as an act of defiance to live and dress as if still in Bangladesh, Pakistan, Somalia or the Middle East. Some say that, in a generation or two, they will assimilate, as other immigrant communities have in the past. But, increasingly, the reverse seems true.

If such self-imposed separation is tolerated or even encouraged, it becomes hard not to arouse suspicion and even anger. The good name of Islam is far from enhanced by almost daily authentic reports of honour killings, forced marriages and Pakistani child sex gangs. Nor are we likely to feel at ease with the Muslim enclaves described by Clarissa when they harbour thousands who would and could do this country harm. We spent a decade deporting rabble-rousing cleric Abu “Hooky” Hamza. Now we seem doomed to waste another getting rid of terror mastermind Abu Qatada."