Although the Christmas Day underpants bomber, Umar Farouk Abdulmutallab, was radicalised during his mechanical engineering studies at the ‘Godless’ university in Gower Street, he was despatched on his way to Detroit by ‘al-Qaeda in the Arabian Peninsula’ (AQAP). This is the flag of convenience for those Saudi jihadists who have merged with their brethren in Yemen after a belated crackdown by Riyadh. The Christmas Day bomb plot meant that Yemen was suddenly discovered by the world’s media as a potential failed state to which the core of al-Qaeda might relocate should the heat in Afghanistan, Pakistan or Saudi Arabia prove unendurable.

This is the jihadi equivalent of the slogan ‘football’s coming home’. The Yemeni Hadhramaut region is the ancestral homeland of Osama bin Laden’s family, his father having migrated to Saudi Arabia as a juvenile remittance worker in the 1925 (not as Clark claims “in the 1930s”). In fact,