Jo Cox, however, was not just any MP doing her duty. She was also an MP who was driven by an ideal. The former charity worker explained what that ideal was as eloquently as anyone could in her maiden speech last year. “Our communities have been deeply enhanced by immigration,” she insisted, “be it of Irish Catholics across the constituency or of Muslims from Gujarat in India or from Pakistan, principally from Kashmir. While we celebrate our diversity, what surprises me time and time again as I travel around the constituency is that we are far more united and have far more in common with each other than things that divide us.”

What nobler vision can there be than that of a society where people can be comfortable in their difference? And what more fundamental tenet of decency is there than to put first and to cherish all that makes us human, as opposed to what divides one group from another? These are ideals that are often maligned when they are described as multiculturalism, but they are precious nonetheless. They are the ideals which led Ms Cox to campaign tirelessly for the brutalised and displaced people of Syria, and – the most painful thought – ideals for which she may now have died.

This was no random event, and the police are investigating reports that the assailant yelled “Britain First” during the attack. This is not merely a chauvinist taunt, but the name of a far-right political party, whose candidate for City Hall turned his back in disgust on Sadiq Khan at the count, in sectarian rage at a great cosmopolitan city’s decision to make a Muslim mayor. The thuggish outfit denounced Ms Cox’s murder, as it was bound to do. But their brand of angry blame-mongering could very well serve to convince particular individuals – especially those who are already close to the edge, as it is reported Ms Cox’s murderer was – that some people are less than human, and thus fair game for attack. The rhetoric of western racism and Islamophobia is the mirror of the ideology with which Isis and al-Qaida secure their recruits and that persuades them to strap explosives to themselves, and die in order to kill. It might be especially powerful in Britain, at a time when divisive hate-mongering is seeping into the mainstream.