If you believe that the history of your culture is nothing but a catalogue of horror, massacre and the oppression of others, then you will not be very assiduous in its defence once it comes under concerted attack.That's from a speech by Theodore Dalrymple, an excerpt of which is posted on David Thompson's blog. It prompts the question, for me, of what brings those who think of Western culture in this way to do so. I'm guessing one quick answer is likely to be that some bodies of ideas which have been influential on such thinking - Marxism, postmodernism - furnish these, its component elements. But isn't that rather too quick? All of the main traditions that have nourished this critical outlook also contained within themselves the resources of a more 'two-sided' assessment of Western culture. Marxism, for example, as critical as it has been of capitalism also emphasized the achievements of capitalism and how these provided the preconditions for something better than capitalism. Mainstream Marxism also stood within the lineage of the Enlightenment, rather than repudiating it as a mere tool of power and domination. No need to spell out that liberalism and other forms of radicalism have, for their part too, seen themselves as standing in the tradition of reasoned argument and the democratic resolution of political differences. And even postmodernism, though it can be used for the most facile of relativizing social critiques, ones sensitive only to the wrongs of 'our' culture, isn't bound to take that direction. There is nothing to stop it from saying (with Richard Rorty) that the achievements of our culture are to be valued just because they are ours.
In sum, within all of these broad outlooks choices are possible. Those who think that the history of their own, of Western, culture is 'nothing but a catalogue of horror' don't think this because they are the prisoners, as it were, of a political ideology allowing them to think nothing else. They choose, within a complex body of ideas, what elements to develop and accentuate and which to minimize or leave alone.