Over here I called the moves "Give" and "Take". We could rename Cooperatebot "Giver" and Defectbot "Taker" and skip the politics. It seems to me that putting political implications such as "trade" and "war" into the game would not make people think more clearly about it, but the opposite.
taking is fine but the entire point of trade is that it's the real life situation that matches cooperation a lot more closely than being in prison with some guy. It's the basis for economics. You don't just "give" you also get.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.