Much is uncertain about how the Muslim Brotherhood will react to the crackdown. With Mr. Morsi held incommunicado and the movement’s other leaders imprisoned or staging a sit-in in Cairo, it is not clear if the coup and violence that followed will shake the Brotherhood’s commitment to nonviolence. But some members will certainly be tempted to retaliate for having political power wrenched from their hands so abruptly.
Erasing the Muslim Brotherhood from Egypt’s political scene — as Gen. Sissi seems intent on doing — is impossible. To attempt it is to play with fire. It could create a schism that would put Egypt on a road toward civil war with dire consequences. Violent uprisings in Syria and Egypt at the same time would be particularly dangerous for Israel, the United States’ strongest ally in the region. Bringing Egypt back from the edge of disaster ought to be one of Mr. Obama’s most urgent priorities, and that may require rethinking his policy. Forbearance and obfuscation haven’t done the trick.