Just in one class that I can remember. "Modern Latin America", taught in the early 80s. Teacher was a full on Communist who would have blown Daniel Ortega in front of the class. Evidently she didn't like my ROTC BDUs or that my stated purpose in taking the class was to learn about our enemies in order to defeat them. Only F I ever got. I was a math major, so most of my profs didn't have enough of a personality to have an agenda.