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Jihadist groups are emerging as a major threat in Egypt because of three developments: the permissive atmosphere for Islamist mobilization in general since Hosni Mubarak's February 2011 ouster, the ruling Muslim Brotherhood's tolerance toward its fellow Islamists, and the weakness of the Egyptian state. To help inhibit violence by such groups, Washington should approach Cairo with a mix of economic inducements, diplomatic pressure, and intelligence sharing.

Groups and Key Figures

Following the 2011 revolution, the military junta that replaced Mubarak granted amnesty to many Islamists, including individuals with blood on their hands. Many of these figures renounced violence, and some established political parties, but others remain completely unreformed. These latter...