There is and there is allot of it
Usally in the responses after choices from the Generals
Do me a favour.. start a new game, just exploit the crazy out of chapter 1 and do everything you wouldn't do in real life

tell me about the defence you get from the undead and the critics from the generals and tell what seems more "real"
Well I'm not going to do that since I don't want to spoil myself on custom campaign, but the next playthrough I'll take on this kind of attitude and see what I come up with. That said my first playthough I made a fair few decisions against my conscience and didn't spot any kind of bias.
One thing I did spot is that it seemed very much like there was a level of judgement in the generals storylines. With Catherine it seemed quite like by supporting women's rights the game was telling me I had done good, if I opposed them it would paint me a monster. I can see Scarlett's path going down a similar route if I oppose equality for gays.
Viewed from an American-centric point of view that could seem biased and politically charged. If a game supports that ideal overtly I'd applaud it, if I game opposed that ideal I'd condemn it. You could argue that's only because it's supporting my views and I couldn't argue against it. At the same time I don't think that's inappropriate.
On other topics, other than that fairly egregious misstep on home defence I haven't detected a particular bias. The game gave me a massive reward for introducing conscription but that never felt like social commentary.