After a stunning referendum defeat for a peace deal with leftist rebels, Colombians are asking what comes next for their war-torn country, which like Britain following the Brexit vote has no Plan B to save an accord that sought to bring an end to a half century of hostilities.

The damage from Sunday’s vote is still sinking in. Instead of winning by an almost 2-1 margin as pre-election polls had predicted, those favoring the accord with the Revolutionary Armed Forces of Colombia lost by a razor-thin margin, 49.8 percent of the votes to 50.2 percent for those against the deal.