There can be no worse offence against humanity than racism. We remember this week the 50th anniversary of the murder of Martin Luther King in Memphis, and we salute what he did for the emancipation of Black Americans. His famous speech, of course, was 5 years previously in August 1963. “I have a dream. That one day this nation will rise up and live out the true meaning of its creed…That all men are created equal.…. And all God’s children, black men and white men, Jews and Gentiles, Protestants and Catholics, will be able to join hands and sing in the words of the old Negro spiritual “Free at last! Free at last! Thank God Almighty we are free at last.” It’s a magnificent speech and well worth reading in full.

Yet 12 months later – in July 1964 - I well remember visiting New York with my parents, witnessing the race riots and gunfire, and seeing notices on the buses “Whites only.” Hard to believe in retrospect.

It had been only a year previously that Nelson Mandela had started his 27 years in prison on account of his campaigning and speaking against Apartheid, which was viewed as being subversive. That allegation may have been more justified against his wife, Winnie, who died this week. Yet even her sometimes violent and revolutionary approach, which was in such contrast to her husband’s pacifism, played an important part in ending that brutal regime. Your ‘revolutionary’ is my ‘freedom fighter.’

All of that might seem like ancient history. But this week we are aghast at the blatant anti-Semitism which has been exposed (despite Mr Corbyn’s protestations to the contrary) at the left of the Labour Party. They mix up their love of the Palestinians, their hatred of the State of Israel, their distrust of capitalism in general with a resulting hatred of demonstrably successful capitalists, the Jewish people, as a whole. Nothing could be more foolish, yet it is alive and well in some parts of the Labour Party today, with for example, Bristol MP Thangam Debbonaire being shouted down at a Labour Party meeting this week because of her outspoken criticism of anti-Semitism in her own party.

Why cannot all human beings, of all classes and religions, of all sexes, and all types, just be treated as human beings, as Martin Luther King so memorably called for 55 years ago? Or can we not remember what Robert Burns demanded some 225 years ago? You remember his poem “A Man’s A Man for A’That.” “Then let us pray that come it may, (as come it will for a‘that), That …. Man to Man, the world o’er, Shall brother be for a’that.”

Pete Seager marched with Luther King from Selma to Montgomery, Alabama in 1965, and coined “We shall overcome” for it. It went on, of course, to become the general anthem for the Civil Rights movement. How prophetic were his words: “When will they ever learn? When will they ever learn?”