Rather than continue trying to respond to various threads arising from the backlash against Diane Abbott's letter and retraction, I thought I'd try to set out my perspective as an historian of colonialism more coherently: 1. Racism and antisemitism are both abhorrent forms of expression, oppression and discrimination which share certain characteristics and have come over time to borrow from one another. However, they are not entirely congruent. They have different genealogies and have had different historical effects. While the identification of antisemitism as a form of racism might help in anti-discriminatory struggles, it is historically problematic to see them as identical and perfectly interchangeable when they can also be distinct. 2. Geneaologies: antisemitism is far longer established than racism. From the medieval period at least it has resulted in vile, abusive language, purges and pogroms. It was of course the main driver of the Holocaust (although racism against Black people also played a part). Antisemitism is pernicious, malleable and persistent. Racism emerged as a coherent 'explanation' and justification for the White supremacy that characterised the European empires during and after the trans-Atlantic slave trade and the abolition of slavery itself, especially as these empires extended into all of the inhabited continents and encompassed a greater diversity of 'non-White' colonised subjects. As well as legitimation, racial distinctions also underpinned the hierarchical structures of colonial governance. Racism too, is pernicious, malleable and persistent. 3. Effects: Racism and antisemitism have had many shared effects but also different ones. Antisemitism has often been more directly murderous. It has resulted in Jewish people being described as 'vermin' and in actions directed at their eradication. Colonial racism can and has had similar effects, also including genocide, but more generally it has been exploitative rather than exterminatory. Racism has supported the maintenance of White supremacy and the domination of Black and Brown colonised peoples' labour rather than aiming their extermination. Hopefully you will see from this that a discussion of differences between these hateful variants of oppression does not in any way imply the minimisation or trivialisation of either one's effects. 4. Let me give an example of how complex the relationship can be: the programme of apartheid was launched in South Africa in 1948 by men who were Afrikaner nationalists, racists and antisemites (Verwoerd had studied for his PhD in Nazi Germany and was inspired by the ideology). But Jewish people were not legally discriminated against under apartheid. Many of them (mainly Communists) were active in the resistance to apartheid because they identified with the persecution that they saw, especially having witnessed pogroms in Eastern Europe. But they were aware that in this instance the legal system they were fighting was racist rather than antisemitic. From their relatively privileged position as White South Africans they saw that that the two forms of oppression were connected but not identical. Surely we should do the same. 4. It is entirely legitimate and not at all antisemitic in itself to discuss these points of difference as well as those of convergence. If we can't do so without being accused of antisemitism, then it becomes very difficult for historians to observe historical specificity. By all means let's define antisemitism as a form of racism if it helps to combat it, but without wishing to defend all the other things contained in Diane Abbott's original letter, let's not round on someone for pointing out that trans-Atlantic slavery, segregation in America and apartheid in South Africa were based on race rather than Jewishness. @Femi_Sorry @kehinde_andrews