"Firefly is not liberal. Neither was Starship troopers (even though the film was a far cry from a wonderful book). Nor was Babylon 5. Oh, and neither was either version of BSG."
Indeed. Firefly was profoundly libertarian. And Heinlein was profoundly libertarian as well. I'm listening to the audio version of Starship Troopers right now. I love RAH's politics. Couldn't get into B5, and BSG was too dark to make me think about anything "political".
Firefly was libertarian but Joss Whedon does not seem to be. Similarly, J. Michael Straczynski, who wrote much of Babylon 5, is quite liberal and atheist but he could write excellent conservatives and religious people. That's the sign of a good author, that they write all people as three-dimensional rather than as straw men for their perspective to knock down. BSG turned into into the tale of the Golgafrincham from Hitchhiker's Guide to the Galaxy without Arthur and Ford. Science Ficiton author Larry Niven is also pretty conservative (see
this interview.