How can US universities combat threat of teaching restrictions?

Voltaire - "I may disagree with what you say but will defend to the death your right to say it"

If politicians outsource their policymaking to academics (e.g. in order to borrow their authority), it is inevitable that their political opponents will begin to infiltrate academia. So it might be wisest for academia and politics to retain distance from each other. It is the same with the legal system.