If the election of Donald Trump signaled the mainstreaming of the “alt-right” in American public life, then the Unite the Right rally in Charlottesville, Virginia, in August 2017, was the point made undeniable. Hundreds of avowed neo-Nazis, white supremacists, far-right militants and Klansmen walked the streets of Charlottesville and the University of Virginia, bearing torches, assaulting counter-protesters, and shouting a cacophony of racist and antisemitic epithets (“Jews will not replace us!”). On the afternoon of 12 August, an avowed white supremacist drove a car into a crowd of counter-protesters, killing 32-year-old Heather Heyer and injuring more than 30 others. That...