Here's a clue: It's been going on since the 1920's. And they've been helping each other, and getting help from people like Moscow Centre and their agents of influcence. I.F. Stone, for example -- a Stalinist. Susan Sontag -- another one. Lots of high-class, hard-core Communist intellectuals -- I'm sorry, make that progressives, their own word for Stalin's men -- sitting around drawing rooms in New York, bad-mouthing the rest of us, ice-picking conservatives in the back, and generally plotting America's demise.
Louis Budenz told us in the 50's that Columbia was Red: but that was an old accusation, broached already 15 years earlier by other Red defectors. So was Indiana University (where, by the way, Alfred Kinsey had his fortress in the 30's and 40's, and invited in people like gay curators from highbrow New York museums to "participate" in his deeply-probing investigation into child sexuality) at Bloomington, back in the 30's; I remember my Indiana relatives talking about IU back in the 50's.
Does that give you an idea?
Don’t forget the thousands of little Maoist’s from the 60’s who moved on from their campus protests to tenured professor.
The rot is so extensive I don’t think there is a cure.