Ross Douthat has an interesting essay out on the reactionary mind. Worth reading, but I have an objection: the term "reactionary" is mostly made up Marxist nonsense, dependent upon the artificial scheme Marx imposed upon history. Communism was the inevitable future of society, and the only people who would resist that bright dawn would be morally deficient "reactionaries."
The term might have a genuine use for someone who really does just want to "turn the clock back," and recreate some earlier time. But such people are few, and to them we can only quote the great philosopher Steve Miller: "Time keeps on slipping, slipping, into the future."
But otherwise the use of "reactionary" is like that of "fascist": "Yuck, I don't like you!" Most people, in fact, think we have taken wrong turns here and there, and would like to reverse those courses. Those on the left often want to return to the stronger labor unions of the 1950s, or the greater concern for social justice seen in the 1960s: are they "reactionaries" for wanting to "turn back the clock" in these regards? Of course not: "reactionary" is something progressives get to call others.