It has been fashionable in recent times for people to engage in race denial (meaning that they claim that race does not exist as a biological reality, but is instead a social construct).
Why deny the existence of race? For the same reason that differences between men and women are claimed to exist only as social constructs.
If you're a liberal, and you believe that we are only human when we are self-determined, you won't like anything that seems to be a biological destiny. You won't want to recognise anything which seems important to us, but which is based on unchosen biology.
Hence the convenient idea that gender and race are social constructs, and can therefore be changed as we ourselves see fit.
Common sense ought to tell us that the liberal theory is wrong. It's not difficult to observe significant differences between men and women across all cultures; nor is it difficult to identify accurately the ancestry of most people based on their physical characteristics.
However, it hasn't really been common sense which has fatally undermined the liberal view. It has been science.
Science has vindicated the conservative view that gender differences are hardwired into us as part of our human nature, rather than being solely a product of culture. We now know too much about sex hormones and the structure of the brain for this to be denied.
Increasingly, too, science is undermining the race deniers. The latest evidence involves genetic research into SNPs (single nucleotide polymorphisms).
Scientists are now looking for genes which are associated with illnesses like arthritis. They have discovered, though, that genes differ according to our broad ancestry. If they control for a person's race (whether someone is of African or European ancestry, for instance) they reduce the amount of "false associations" in their research.
Already, scientists have found SNPs correlating to our continental ancestry (African, European, Asian etc). Now, SNPs have been identified which show not only European ancestry, but which distinguish between those of Northern and Southern European descent.
So as a by-product of medical research we have it confirmed that there is a biological basis not only for broad continental differences in race, but even for intra-continental ones such as those between Northern and Southern Europeans.
And scientists are now starting to investigate distinctions within the other continental groupings (which they will surely find).
I wonder how long it will take for such research to become commonly known and to complicate the established liberal views on race?