I noticed it first after 9-11 and Letterman, which was more conservative and nationalistic but I never saw Vietnam era late shows, though I doubt it was anywhere near as blatant, tho perhaps it was. The little I've seen with Carson, he seemed to joke about both sides and not let his conservative side show much. But now every single one is a far left libtardfest. Just stfu and make jokes, not political screeds.