Columbia University and Communism
Columbia U was chosen by immigrants from The Frankfurt School (Germany) to be their US HQ for advancing their social Marxism agenda for making America socialist.
They coopted professors in other teaching colleges, to indoctrinate their students to be Marxism-friendly. Then, take that to the public schools they would soon be teachers in. They got into the NEA and other unions.
Many many Marxist-friendly big players went to Columbia U and are in positions of power now. One in particular is Obama.