Why is it that the AI can warn you about removing ships and or star bases but the player can't.  I think the diplomacy feature needs some work.  Yes your allowed to trade but it doesn't give you the option to intimidate the AI. For example in GC2 you were able to either beg or intimidate the AI for free stuff.  In GC3 it seems you have to trade something for something.  When trying to get payment from a weaker AI you have to trade for it vs just telling them that this is tribute for not making them part of your empire.