I'm not certain it's fair to lable pragmatism as liberalism.
But don't you see, we HAVE to be liberals in order for them to feel morally superior to them.
"Pragmatism" is usually another word for shortsightedness, in my opinion. To put it another way, the short term gains that might be gained by the compromise of core principles is usually negated by the much worse long term consequences of that compromise. The evidence? The long term erosion of our constitutional form of government.
Beyond that, it is hard for me not to label folks who regularly attack conservatives as liberals. If they're not liberals, I don't know how to can discern any measurable difference, given their tactics and seeming goals.