Karachi is a city of migrants and an important commercial hub, which provides Pakistan with a window on the world. But Karachi is also a deeply fragmented city, plagued by an acute urban crisis that takes roots in the failure of the development plans that successive Pakistani governments have delegated to foreign experts. The transnationalisation of the Afghan jihad, in the 1980s, also fuelled social and ethnic antagonisms in the city and contributed to the proliferation of violent entrepreneurs and ethnic parties. Both criminal elements and ethnic activists contributed to the ever-increasing fragmentation of urban space in the city, and to the multiplication of ethnic enclaves controlled by private militias. This extreme fragmentation of the city has benefited local jihadis and foreign terrorists who have taken shelter here since the fall of the Taliban regime in Afghanistan. However, Karachi will never be a “sanctuary” for jihadi militants, due to the hostility of local ethnic parties, whose activists see themselves as enlightened secularists at war with the most retrograde elements of their society and their foreign allies.