Personally, liberal students scare the shit out of me. I know how to get conservative students to question their beliefs and confront awful truths, and I know that, should one of these conservative students make a facebook page calling me a communist or else seek to formally protest my liberal lies, the university would have my back. I would not get fired for pissing off a Republican, so long as I did so respectfully, and so long as it happened in the course of legitimate classroom instruction.
The same cannot be said of liberal students. All it takes is one slip—not even an outright challenging of their beliefs, but even momentarily exposing them to any uncomfortable thought or imagery—and that’s it, your classroom is triggering, you are insensitive, kids are bringing mattresses to your office hours and there’s a twitter petition out demanding you chop off your hand in repentance.
Well, every leftist enclave eventually eats itself, and academia has become a leftist enclave.