At the start of Welcome to the Mosque (30 September), film-maker Robb Leech mentioned that he has “a complicated relationship with Islam”. Indeed he does.Leech has previously made two documentary films about his stepbrother, Richard Dart: the first when he turned to radical Islam; the second when he was jailed for terrorism offences. In this film, though, Leech wanted to feature ordinary Muslims and approached the East London Mosque in Whitechapel, the country’s oldest and largest mosque, used by 2 million worshippers every year. It practises a conservative brand of Islam; nonetheless it let him in.The mosque has come a long way. Before the current structure was built, in 1982, worshippers had gathered in a variety of places including a Portakabin. Now its vast building