This aspect of human cultures is not restricted to white Caucasians. There are innumerable examples from other cultures as well, many of which persist today.

There is not a shred of scientific evidence that a person’s skin colour has any material bearing upon their intellect or character.

DNA studies reveal that skin colour is amongst the most trivial of variations in human beings, being simply an adaption to differing climatic conditions.

The persistence of racist beliefs reflects the unpleasant fact that a large number of human beings are insensitive, ignorant and rather stupid about this specific issue and many others besides.

This helps explain why Adolph Hitler and his criminal cronies could win 44% of the vote in the 1932 elections in Germany, with the population then doggedly following their Fuhrer to catastrophe even when the true nature of Nazism was evident.

In a similar way, a distressingly large minority of Americans feel so threatened by their coloured fellow citizens that they will throw their support behind a narcissistic sociopath who is devoid of insight, empathy or much in the way of intelligence.

Racism is what might be called a “wicked problem”, in that there seem to be no immediately effective ways to counteract it beyond endlessly repeating that it has no basis in fact and invariably leads to great injustice and suffering.

Some academics believe that the incidence of what might be called ‘pure’ racism has diminished markedly, at least in the democratic world.

The recent enormous popular support across the world for the Black Lives Matter movement is fairly clear evidence that this is indeed the case.

On that basis, it is reasonable to conclude that we probably now have an irreducible minimum number of hard core racists in our midst.

In Australia, I would suggest that the proportion of the population who fit this category is no larger than around 5%.

I say this because as long ago as 1967 some 91% of eligible voters cast their votes in favour of removing blatantly discriminatory laws that reduced Aboriginal people to the status of non-citizens.

Unhappily, a much larger proportion of the population is in the category I mentioned earlier, being insensitive, ignorant and stupid.

They can be easily deluded into supporting actions and behaviours that are racist in nature without even comprehending that this is the case.

For example, the persistent large scale abuse of Aboriginal footballer Adam Goode in the latter stage of his career was carried out by people who, when asked, declared that they were not being racist but merely expressing disapproval of how he played the game.

Only later did it dawn upon some of these people that their actions were being understood by Aboriginal people as racist even if they didn’t share that understanding.

I agree with Michael Dom that the starting point for eradicating these baseless and harmful ideas lies in personal insight followed by moral action.

As I am sure Michael knows, this is much harder to achieve in practice than in theory. Entrenched ideas about the world die very, very hard indeed.

This being the case, our political class must resign themselves to the very long term task of, firstly, suppressing racist behaviour wherever it occurs and, secondly, striving to change attitudes about race. The latter task is much harder than the former.

In the case of policing in the USA, this must include relentlessly training police officers to understand the socio-economic contexts within which they are working, as well as seriously attempting to reduce their apparent reliance upon heavy handed and even lethal force as all too graphically displayed in the case of George Floyd.

The number of deaths in police custody in the USA is twice as high as that in Australia and six times higher than in the UK.

As Phil Fitzpatrick has indicated, there is an underlying issue at work here, being the exploitative and deeply unfair nature of American capitalism.

Until that it dealt with, I suspect that there will be little other worthwhile change to the current situation of non-white people in the USA.