In the post-9/11 era, an increasing number of extremist threats are homegrown. Radical organizations such as the Islamic State are actively targeting Muslim immigrants and nationals of Western countries as recruits. Yet, little research has addressed the factors that drive immigrants to aggress against their country of settlement. We integrate the terrorism and immigrant acculturation literatures to suggest that cultural identification processes play a key role in the radicalization of Muslim immigrant and minority populations. Specifically, we propose that "marginalized" immigrants who do not identify with either their heritage culture or the culture of the larger society (Berry, 1970, 1997) have experienced significance loss (Kruglanski, ...