The RAND Corporation started out as a USAF think tank. RAND stands for Research and Development, and the organisation was designed from the ground up to get a bunch of eggheads in a room to come up with high tech advanced info for US military (and i would say Deep State) decision makers. I would not say they were liberal.
There is a reason why Stanley Kubrick, in his famous film, Dr. Strangelove, had the good doctor himself quote a fictional "Bland Corporation" when describing the mine shaft strategy and so forth.
That is how I see RAND - advising the high muckety-mucks in Washington.
I do not consider them to be liberal. It is RAND, after all, who are instructing leaders in DC on how to "win" a nuclear war. Just like in the movie.