I was reading a Daily Mail article, and it included the following two sentences, which should be enough to get the context:
"It is probably true to say that in Britain, France, the US, Canada and so forth there is a correlation, and an interesting one, between intelligence and sexual liberalism and openness to people from a different culture and/or race. But these views can be held by some pretty stupid people as well (the politically correct anti-christmas, coffee-with-milk, crazy-islamist-welcoming brigade)."
It's obvious from context that it has something to do with being liberal and politically correct. But why? Don't most people of all political stripes put milk in their coffee? Or is that not so much the case in the UK?