Excellent discussion of the term "cultural Marxism" and it's sudden popularity with folks on the right--from David Brooks to David Duke. Short version, it's little more than good old fashioned anti-semitic Red baiting. s-usih.org/2018/12/a-far-…
I'm working on a longer piece about this and am still formulating my ideas...but basically, what Brooks calls "cultural Marxism," is what most academics would call sociological, anthropological, literary, or historical analysis as done by anyone who went to college from 1990 on.
You will be shocked to learn that most of the critics of so-called "cultural Marxism" either went to college before the 1990s or went to one of the handful of conservative (or Christian) colleges designed to be safe spaces insulated from such modes of thinking.
The entire enterprise depends upon a willful and cynical misreading of what's been happening in the social sciences and humanities for the past 30 years. "Cultural Marxism" is anti-intellectualism for people who want others to think of them as intellectuals.
For example...here's Infowars guy tweeting out Andrew Breitbart's painfully obtuse (willfully misrepresented?) summation of "what I was taught in college." "Cultural marxism" is the term the alt-right uses to give supposed academic heft to their reactionary anti-PC stance. 
Here's is a rough genealogy of "cultural Marxism" as political meme...from Andrew Breitbart to InfoWars to Charlie Kirk to the President of the United States. Trump has merely accelerated the far right's longstanding effort to take over the @gop.
What I find most interesting about the term "cultural Marxism" is the way it helps us to see the connections between a) far right/reactionary politics stretching back to the early 20th century and b) the anti-PC culture wars of the early 90's that came to define the @gop brand.
The term "Cultural marxism" traces an arc from George Lincoln Rockwell and Father Coughlin, up thru the John Birch Society and Pat Buchanan, and now all the way up to Charlie Kirk and the current President of the United States.
