Sean in the comments to Lydia's post below observed that, according to Richard Rorty:
... the fact that we just don't accept the triumph of the sexual revolution and last Thursday's discovery that a man's ability to marry another man is a most fundamental human right means that we are the moral equivalent of defeated ex-Nazis?One of the most delicious and horrifying ironies of our modern/postmodern condition is that the Nazi, who is a heretic from liberalism precisely because he makes the Low Man (and programs for his extermination) completely explicit, now counts as the paradigmatic Low Man himself. So any Low Man (e.g. someone who doesn't buy into last Thursday's discovery etc.) is, for all practical purposes, a Nazi or Nazi-in-gestation. A further irony is that the liberal and his close-cousin heretic the Nazi have much more in common with each other than the actual men that both see as the Low Man (other than each other), the actual politically subhuman roadblock in the way of the triumph of the will of the free and equal new man, self-created through reason and will, living under a value system created by man himself and not subject to natural or traditional hierarchies and authorities, politically subject only to himself and most especially not to God or other men. Man may be subject to God in his private life and by private choice, so long as this in no way interferes with the free choices of other men. But politics must be the instrument of man's free and equal will and only man's free and equal will: no God allowed.
I'm not sure this is fully conscious on the part of the liberal himself though, in this sense: the liberal himself is often (ironically) one of the most narrow-minded human beings to ever exist, and is generally incapable of seeing modes of thought farther away than the tip of his nose. Because the Nazi is no farther away from the liberal than the tip of his nose, he understands the Nazi and is rightly horrified by the Nazi's evil. Anyone even further away than the tip of his nose thus cannot be anything but a Nazi. The notion of a non-Nazi illiberal or anti-liberal is inconceivable, or is ruled out a priori.
Some might see it as ironic or claim that it is false that the anti-liberal is more open minded than the liberal. The anti-liberal, after all, is authoritarian, traditional, sees value in stereotypes, takes nature's physical and moral constraints as a given, does not think human beings are or ought to be equal in every respect, does not have a cow over discrimination-qua-discrimination, etc. But this only seems narrow-minded from the narrow-minded liberal perspective. Who is more open-minded: the man who recognizes that scientific knowledge has inherent limits even within the scope of material things, or the positivist who closes his eyes to such limits and cannot conceive of anything but postmodern catastrophe if such intrinsic limits are admitted? Who is more open-minded: the man who recognizes that traditional sexual morality is written in nature and is necessary for a healthy society, or the man who closes his eyes to that truth? Who is more open-minded: the man who recognizes that men and women are different in fundamental ways and cannot be forced into generic identity (equality) without destroying the social fabric, or the man who closes his eyes to that truth? Who is more open-minded, the man who insists that nothing but material things exist and there is no God despite his own experience of consciousness, love, beauty, moral right and wrong, etc; or the man who does not so insist? Who is more open-minded: the man who recognizes many hierarchies and natural inequalities among human beings themselves without those inequalities implying the untermensch, or the man who cannot admit the existence and goodness of particular inequalities without that implying the untermensch?
I could go on all day, but the point must be granted: the man who deliberately closes his eyes to the unwanted truth, the truth that man is infinitely less than God and in some manners, times and places is less than his fellow man, is more closed-minded than the man who recognizes the truth.
Something that the postmoderns have right, though (ironically) not at all in the way they think they have it right, is that one of the most pervasive features of modernity is irony.