Originally Posted by IncoherentEssay
Still, if anyone who does Res on a given turn cannot defend before the next turn rolls around, either large amounts of manpower or Res-specialists seem necessary, depending on how aggressively the AI acts. Does upkeep depend on quality, quantity or both?
You get upkeep per unit, with the actual cost depending on the unit.
Also, the AI's attacks are easy to fend off. Mostly. It's not really all that aggressive, though there are two or three times in the game when it gets a bit tricky.