I'd agree with your political leanings there :) I guess when I saw it I just ignored that part of it and tried to watch it straight.
Most definately not; he graduated from Annapolis, served five years, and reached the rank of Lieutenant in the Navy before having to retire due to health reasons. He remained very pro-military, all his life.
Good--I'm relieved to hear that :) When I was originally introduced to him I had heard people accuse him of being pro-fascist, largely on account of Stranger in a Strange Land and the way it was being interpreted in the 60s (like what Charles Manson did with it). But I haven't seen any actual evidence of that in what I've read so far--I suspect that's a left-wing take on him. What were his actual political views?
It's generally held that he was strongly Libertarian in his views; different from modern Libertarians though, in that he believed in a strong national defense, and strictly maintained borders.