I often find myself, in the mid or late game, coveting some resource that's only available in an AI civ's territory and that the civ in question has already traded away any surplus of, with none remaining to trade to me. Of course, I could try to obtain that resource through conquest, but that may not always be desirable.
The peaceful option is to figure out what other civ they're exporting that resource to and then try to get them to break off trade relations, so that the resource becomes available for trading again. However, that's not always possible either. I've tried figuring out what other resource they're receiving in exchange for the one I'm after, and then sending spies into that other civ to sabotage all the tile improvements supplying that resource. I was assuming this would cancel the relevant trade deal between the two civs, but that didn't happen when I tried it. Are there any approaches that would work?
The peaceful option is to figure out what other civ they're exporting that resource to and then try to get them to break off trade relations, so that the resource becomes available for trading again. However, that's not always possible either. I've tried figuring out what other resource they're receiving in exchange for the one I'm after, and then sending spies into that other civ to sabotage all the tile improvements supplying that resource. I was assuming this would cancel the relevant trade deal between the two civs, but that didn't happen when I tried it. Are there any approaches that would work?