Donald Trump will be the Republican candidate for president. He might even become president of the US. It is hard to exaggerate the significance and danger of this development. The US was the bastion of democracy and freedom in the 20th century. If it elected Mr Trump, a man with fascistic attitudes to people and power, the world would be transformed.

Mr Trump is a misogynist, a racist and a xenophobe. He glories in his own ignorance and inconsistency. Truth is whatever he finds convenient. His policy ideas are ludicrous, where they are not horrifying. Yet his attitudes and ideas are less disturbing than his character: he is a narcissist, bully and spreader of conspiracy theories. It is frightening to consider how such a man would use the powers at the disposal of the president.

Andrew Sullivan, the conservative commentator, recently wrote: “In terms of our liberal democracy and constitutional order, Trump is an extinction-level event.” He is right.