British Prime Minister Theresa May was handed a historic and humiliating defeat Tuesday when parliamentarians rejected her proposal to withdraw the United Kingdom from the European Union. Mass defections from her own party have left May scrambling to come up with an alternative plan with 10 weeks until the scheduled departure date of March 29. May has no good options; a delay in withdrawal is possible, but so too is a second referendum — or the catastrophe that is a "no-deal Brexit."

May's government spent two years negotiating the terms of withdrawal — working out the framework for future relations with the EU is the next assignment — squeezed by Brexit supporters' demands for maximum benefits from the EU while reasserting British sovereignty over other policies and the EU's recognition that such a deal would spell the end of the union as other governments sought similar arrangements. The result was a 585-page document that made almost no one happy.

The depth of that disaffection was quickly apparent, forcing May to postpone the first parliamentary vote on the agreement originally scheduled for December. The delay was intended to give the government time to make its case for the deal. It failed.