As Mohammed Siddique Khan led his group of fellow-believers into London on the morning of 7 July 2005 it is unlikely that they were thinking much beyond the immediate impact of their actions. Driven by anger at the West’s treatment of Muslims worldwide, ideas fed to them by foreign extremists, and a sense of extreme rejection of the society in which they were born, they sought to reshape the world in an image they thought would be pleasing to God. Pantucci offers an insight into the motivations behind Khan and his group, as well as the hundreds of young British Muslims who have been drawn by jihadist ideas to fight on battlefields at home and abroad. Pantucci is Director of International Security Studies at the Royal United Services Institute for Defence and Security Studies.