As I sat down to write this post, on Thursday morning, there was a week to go until the British referendum on whether to leave the European Union, and a “Leave” vote was looking like a live possibility. Politicians who had endorsed a vote to “Remain” were getting nervous, and the financial markets were gyrating with every new opinion poll. As for the British people—well, until Thursday lunchtime many of them were busy watching the Euro 2016 soccer tournament, which is being held in France. Then, Thursday afternoon, came the shocking news about the brutal murder of a Member of Parliament by a man who, reportedly, shouted “Britain first!”—the name of a far-right organization that is virulently opposed to immigration and to the E.U. The killing took place in Birstall, a small town outside the city of Leeds, in West Yorkshire. The victim, Jo Cox, was a forty-one-year-old mother of two, and a widely respected representative of the opposition Labour Party, which has joined the Conservative Prime Minister, David Cameron, in calling on Britons to reject the Brexit option and vote “Remain.” According to eyewitness reports cited by BBC News and other media organizations, the attacker approached Cox as she was leaving a meeting with constituents, shot her several times, and then stabbed her numerous times as she was lying on the ground bleeding. Following the attack, Cox was airlifted to a hospital, but she died soon after. Police, meanwhile, arrested a suspect—news reports identified him as Tommy Mair, a fifty-two-year-old local handyman. Out of respect for Cox and her family, both sides in the referendum suspended their campaigns for the day. Cameron called Cox’s death “tragedy.” Boris Johnson, the former mayor of London, who is the leading politician on the “Leave” side, described it as “horrific.” And Cox’s husband, Brendan Cox, released a statement saying that she would have wanted people “to unite to fight against the hatred that killed her.”