by Halfinger
I find it easier to think of where a side should be at various stages in the game. A score of 0 does not mean the sides are even, it means one or the other side did not optimise their play up to that point. The game is balanced, just not around one particular score at a given time. When the score goes naturally against me I simply focus on damage limitation to ensure it does not tip over to a win for them. This seems to work for me. So as the US I win most games.I know this is a vague reply but I found this mindset the best to start playing well, at least for me.
I do include the optional cards but really those and the variants seem to do little when compared with better play until you get very experienced with the game and every point really counts.