"where, indeed, the main current of campus conservatism did seem to be
Catholic monarchism merged with Austrian economics - a phenomenon for
which I would still appreciate an explanation"
American university student conservatism tends towards these highly incompatible extremes because American university students are 18-22 year olds who wish to rebel against the status quo, and for whom moderate left-liberalism can constitute a status quo no less than religious fundamentalism or small-town conservatism. Some kids go in for Neitzsche and critical theory, some go in for in-your-face atheism, some go for drugs, some go for Catholic monarchism merged with Austrain economics. The fact that they're incompatible makes the act of rebellion that much more rebellious.
But, like all adopted college personas, the extremes mostly fade over time. Worry more about the 25 year-old who still holds to both.