I know. I just like to.
Um, no, not that I've noticed. Yes, it's a tendency of American pundits and public intellectuals-- but on the Right, not the Left. Any leftist I'm familiar with insists that human rights are universal. They're always harping on that UN Universal Declaration (you know, the one the US signed and routinely ignores). It's the Washington establishment, in my experience, that uses the "cultural differences" excuse to prop up nasty regimes from Buenos Aires to Jakarta. Unless you're redefining "the Left" to include Rockefeller Republicans like Clinton, then I don't see it.
There is another kind of "cultural relativism" that leftists and other socially enlightened persons tend to recognize, but it has nothing to do with revoking the human rights of brown or yellow persons. It's more about the observed fact that norms and mores may differ from culture to culture, so that smoking weed (for example) might be taboo in one culture and acceptable in another. The Right criticizes this kind of "cultural relativism" when they set about legislating their morality, but they misappropriate it whenever they need an excuse to subvert human rights.
It may well be different in America, but one could certainly point to a significant section of British and European academia and call it both culturally relativist and leftist/anti-American. I wasn't refering so much to regimes and governments per se - and I'm sure you're right that it is the Right who defend this, through self-interest, with relativism. I was thinking more of those of us who defend traditional societies in Africa, Asia, the Arab world, etc, and who see our involvement with them as interfering or imperialist. (I used to have sort of a Burkean view of the world, regarding anything ancient as venerated and therefore justified by having worked for so long, but I would no longer say that I quite subscribe to this.) I find this sort of moral/cultural relativism, call it what you like, rather dangerous, as it tends to act as a barrier to the spread of universal human rights and so on (though I'm certainly not defending the hypocrisy of our own governments in this regard either).
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