In Germany, it is a Brandmauer, a firewall. In France, it is the cordon sanitaire – a refusal by mainstream parties to do deals with the far right. That resolve has weakened in recent years, but naming the taboo still serves an important function. To invigilate the line where radical conservatism turns to ultranationalism, it is first necessary to say it exists.
That is not happening in Britain, as has become clear in the aftermath of Henry Nowak’s murder. The episode is disturbing. Police failed to recognise the severity of a young man’s stab wounds and, after being misled by a false claim that he had carried out a racist assault, briefly treated the dying victim as a suspect. However difficult and confused the scene was, this was a catastrophic outcome. It is right that every aspect of the case be thoroughly reviewed.