From the vantage point of a news helicopter, the hundreds of thousands of people who lined the streets of Central London on March 23 looked like a colony of ants. The thick column stretched from Hyde Park in the west past the Ritz Hotel before spilling out in front of the Houses of Parliament. Broadcast on loudspeakers and carried aloft on placards came the marchers’ demand: “Put it to the people.”

What else could “it” be but Brexit? Nearly three years after the June 2016 referendum in which 52% of voters elected to leave the European Union, the country is both divided and paralyzed by the decision. And on March 27, after two defeats from lawmakers who refused to ratify the exit deal she negotiated with the E.U., Prime Minister Theresa May made one last attempt to end that paralysis by promising to resign if Parliament would just push her deal over the line.

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