The book challenges the conventional discourse on – and responses to – contemporary terrorism. It examines the synergy between the extremist ideologies and the organizational models of non-state actors that use terrorist means in asymmetrical conflict. This synergy makes terrorist groups so resilient in the face of the counterterrorist efforts of their main opponents – the state and the international system – who are conventionally more powerful. The book argues that the high mobilization potential of the supra-national extremist ideology inspired by al-Qaeda cannot be effectively counterbalanced by the mainstream global ideologies or even by moderate Islamism. In contrast to the more localized grass-root movements that combine Islamism with nationalism, autonomous cells of al-Qaeda-inspired transnational violent movement do not defend territory, nation, or the state. They fight for an all-embracing mode of existence, for a global social, political and religious order based on their radical ideology. Unless the ideology of violent Islamism is ‘nationalized’ and its organizational forms are transformed within the national political context, it is unlikely to be amenable to persuasion and external influence or to be destroyed by repression.