Left, right, Harris, Trump: all prisoners of political nostalgia in an era few understand | Rafael Behr

The digital age has turbo-boosted extremism, and analogue democracy is struggling to keep up

Donald Trump's record of refusal to concede defeat after the last US election should have disqualified him from running in this one. His criminal indictments should have meant banishment from mainstream politics. His campaign rhetoric - a rambling litany of bigotry and spite - should not have carried beyond the paranoid fringe.

But what use are should and shouldn't against the brute force of can and does? Things that are supposed to be self-evident in a constitutional democracy have ceased to be obvious to millions of Americans. We don't need to wait for all votes to be counted to wish for a stronger cultural inoculation against tyranny.