I found the article by Dr Sariya Cheruvallil-Contractor (“The British face of Islam”, 5 July) informative but superficial. In discussing Sunni and Shia Islam, she completely omits the bloody origins of the disputes between them, with the main one being the martyrdom of Hussein (Ali’s son) which is graphically commemorated in public processions on the Shia streets every year.The Shia have never forgiven the Sunnis for that, and the civil wars in Syria and Iraq are but the latest episode of a long conflict between them. What has added to the intensity this time is the simultaneous resurgence of Sunni extremism whose aim is to drag Islam back to seventh-century Arabia, with the restoration of the caliphate and the full application of the sharia. The Salafis and Wahhabis, wh