Graeme Wood discusses The Way of the Strangers: Encounters with the Islamic State, his intimate new account of what drives the jihadi group’s true believers.

Experts discuss the Zika virus health emergency, its impact on Brazil, and actions that need to be taken to prevent a crisis.

Experts discuss Friday’s attacks in Paris, violent extremism in Europe, and possible connections to terrorist movements in the Middle East and elsewhere.

ISOBEL COLEMAN: Good afternoon. Good afternoon, everyone. Thank you for joining us here today. I'm Isobel Coleman. I'm a senior fellow here at the Council on Foreign Relations and director of the Ci…