American politics has long been conducted in the shadow of violence. Two of the country’s most celebrated presidents — Abraham Lincoln and John Kennedy — were assassinated. During the 1968 presidential election campaign, Bobby Kennedy was also assassinated, five years after the killing of his brother and two months after the murder of Martin Luther King, the civil rights leader. Ronald Reagan was also shot and wounded in the early years of his presidency.

It is this history of political violence that makes Donald Trump’s suggestion that American gun owners could somehow stop Hillary Clinton so incendiary and dangerous. It is difficult to listen to the Republican nominee’s remarks and to regard them as anything other than an oblique, but unmistakable, suggestion that somebody might try to kill his Democratic rival rather than see her appoint liberal judges to the Supreme Court.

The Trump campaign’s spin that he was merely appealing to “Second Amendment people” to get out and vote is unconvincing. The statement was made in the context of a discussion of how the US would look once Mrs Clinton had been elected and started appointing judges. There would, said Mr Trump, be “nothing you can do” — before musing aloud, “although the Second Amendment people, maybe there is”.