On November 19 1919, the US Senate repudiated the Versailles Treaty. With that decision, the US withdrew its might from maintaining what had been agreed in the aftermath of the first world war, leaving this task to the British and French, who lacked both the will and the means to do so. The second world war followed. After that conflict, the US played a far more productive role. Today, the world is still in many ways the one the US made. But for how much longer will that be the case? And what might follow it? The outcome of the next presidential election might answer these questions, not just decisively, but, alas, very badly.

Recent polls suggest that almost 55 per cent of US voters disapprove of Joe Biden’s performance. They also suggest that Trump is slightly ahead of Biden in head-to-head polling before the election now a year away. Finally, they suggest that Trump is ahead of Biden in five of the six most important “battleground” states. In all, a Trump victory is clearly and disturbingly plausible. (See charts.)

What would that mean? The most important answer is that the US, not just the world’s most powerful democracy, but its saviour in the 20th century, is no longer committed to democratic norms. The most fundamental of such norms is that power has to be won in free and fair elections. Whether US presidential elections are “fair” is debatable. But they do have rules. Efforts by the incumbent to overthrow those rules amount to insurrection. That Trump attempted to do so is not debatable. Neither is the absence of evidence of fraud to support his attempted coup. He is properly under indictment. Yet he might still win a presidential election. One reason why he might do so is that close to 70 per cent of people who identify as Republicans say they believe his lies. This is shocking, though, alas, not that surprising.