International Conference: Current Security Challenges for the Western Balkan Region Addressed by Means of Joint Responsibility and Cooperation attack, that Muslims have a duty to defend their fellow Muslims worldwide, and that they must establish the Caliphate in order to mount this defense. However, they refrain from specifying exactly how Muslims should do so. Nevertheless it can be argued that, while not openly endorsing violence, they provide powerful ideological tools to radicalize Muslims. The jump from embracing the Salast or HT's worldview to committing violent acts in order to further its goals is, according to many, a short one. For this reason, these groups are often identied as a“conveyor belt” to terrorism. 15 represents a major security concern for the Continent. Moreover, there are indications that larger numbers of young European Muslims, while not fully embracing jihadist ideology, adopt some of its frames and ideas. PARTICIPATIONISTS At the bottom of the pyramid is the numerically most signicant component of political Islam in Europe: the Muslim Brotherhood and other“participationist” Islamist movements such as the South Asian Jamaat-e Islami(whose inuence is largely limited to Great Britain) or the Turkish Milli Görüş 23 (headquartered in Germany, but active in all European countries with a sizeable Turkish population). Unlike rejectionists, such organizations have made a conscious decision to avoid unnecessary confrontation and have instead opted for a clever and exible policy of engagement with the European establishment. The history of participationist Islamist organizations in Europe began approximately fty years ago, when many members of the Muslim Brotherhood, who were often eeing persecution in their home countries, spent signicant amounts of time or permanently settled in various European countries. These“European Brothers” founded some of the rst Muslim organizations in the West, which at the time of their foundation were little more than student organizations with a few hundred members. At that point, most of these individuals and organizations simply aimed at spreading the Brotherhood's ideology to the small number of Muslims living in Europe, while focusing their political efforts on inuencing their native countries in the Middle East and North Africa. 16 15 Zeyno Baran,“Fighting the War of Ideas,” Foreign Affairs(November/December 2005). 16 Lorenzo Vidino,“The Muslim Brotherhood's Conquest of Europe,” Middle East Quarterly 12:1(Winter 2005), pp. 25-34.