The death in police custody of the 46-year-old African American George Floyd in Minneapolis put a match to a powder keg. The heartbreaking video clip of him pleading for his life with the words, “I can’t breathe”, and the refusal of the officer concerned to heed his plaintive cries, minute after agonising minute, seemed to typify the brutish thuggery of White Supremacy when it puts on a uniform and exerts its power.

As news of Mr Floyd’s death spread, peaceful protests soon turned into riots. Attempts by the police to regain control of the streets whipped up further antagonism towards them. The picture was repeated across the United States as riots engulfed city after city. This was not just copycat rioting, as deep Black resentment towards the police already existed. The demonstrators’ slogan “Black Lives Matter” only makes sense against a background assumption that, generally speaking, they do not. The American broadcaster CNN listed 12 recent cases where African Americans had died at the hands of law enforcement officers. There have been three convictions.