Have you contacted them and asked for the starbase? Or traded for it? They'll probably turn you down, but if your military is strong enough they might hand it over ...

Well, culture wars is part of the game.Tough.

I would have to agree, an alien race should not just be allowed to set up shop within your established borders. The attempt to come into your space should be questioned unless invited. Having the option to say "get out of my space or else" adds abit of reality, you wouldn't see the Russians coming over to the United States and saying were going to put our stuff here and this land is ours and there is nothing you can say about it. I think if it was done well it could really help the diplomatic game.

I would have to agree, an alien race should not just be allowed to set up shop within your established borders. The attempt to come into your space should be questioned unless invited. Having the option to say "get out of my space or else" adds abit of reality, you wouldn't see the Russians coming over to the United States and saying were going to put our stuff here and this land is ours and there is nothing you can say about it. I think if it was done well it could really help the diplomatic game.

In GalCiv races don't claim deep space, only worlds. Building a starbase near to your colony isn't considered invasion and a cultural starbase isnt a military incursion. It's a big embassy. A better analogy for your Russians setting up shop in American 'territory' would be the Soviet nuclear missile silo's built on Cuba in the 1960's. Although Cuba wasn't American soil it is right next door and the Americans didn't think it was acceptable. The situation was resolved through agressive maneouvering and the threat of war, America blockaded Cuba and the Russians were forced to turn the ships carrying missiles around or engage the American navy.

I have traded for them, I also would place warships next to it and give them to an empire that they were at war with.

I love that solution!

Building a starbase near to your colony isn't considered invasion and a cultural starbase isnt a military incursion.

It's still intentional conquest. You can feel better about it since you're not blowing people up, but at the political level, there's not that much difference.

Oh, I'm not saying that they should be restricted because it's not their territory. I'm just saying that the current AI thought is that you're attempting extortion, so they won't give in unless you're significantly more powerful than they are. They should take into account such things as relative importance. A cultural starbase right next to my home world is definitely something that I would consider risking going to war over, but unless it's key to the other players strategy against me (in which case negotiations are useless anyway), it's probably not worth it to them to go to war over.

I'm just saying that the existing diplomatic options are even heavier-handed than the reality of such situations, and I'd like an option that expresses an opinion other than "I'm a slavering, warmongering fool who thinks you're my next victim."

Maybe an option for decomissioning rather than handing something over. Many times I got into war with the GC1 AI because it would demand that I hand over cultural starbases in contested areas. I'd be willing to destroy them, but hand them over? Much less likely.

As for the placing warships next to it and trading, my preferred tactic in GC1 was a "sufficient" stack of antimatter missiles, a starbase to make sure they were in range, and then form a circle around them and the starbase in question with constructors if a resource SB, or some other cheap ship otherwise. That way, noone would get in or out until I got what I wanted. You'd be amazed how often the AI took a dozen or more turns to decide to attack the starbase