John, I agree completely with your analysis. I think you could underscore your point with a review of the recent history. The progressivist left was at some points enthusiastic about the Soviet Union and was never excited about opposing it, even when it was obviously a totalitarian nightmare. They’ve always been into Castro’s Cuba with defenses based on how many doctors Cuba has or how many people can read. Never mind the cars are all about 40 years old and buildings are literally crumbling. And what about the failure of free political discourse, voting rights, property rights, etc.? “There are other important rights than civil rights. There are economic rights,” the apologists say.
How libertarians could get along with a movement that was essentially a fellow-traveler to a total government solution is beyond me. And now oil-fueled communism is rising in our own hemisphere. Libertarians definitely have to flank to the right.