It was about 1700 ad and I was trying to catch Persia. Japan was behind the curve tech-wise and so Persia decided to declare war on them. Persia, of course, was rolling until I gave Japan rifling (calvary). That slowed the war down to a defensive struggle. Later, I gave Japan the railroad (machine gun) and then Persia really had its hands full. They were so focused on winning that war, massing and throwing armies agianst those machine guns, their score dropped to the middle of the pack, essentially taking them out of the game by 1900. I try not to fight a war some second rate nation can do for me.

Smart! I'm trailing Saladin and Washington right now on points. Can't wait for any one of them to get in a war with anyone heehee.

Of course the blow back is that such blatant trading means the civ you're trying to hamper will hate you. But, hopefully they'll be stuck in a quagmire and wont be able to do anything about it. By the time the war ends hopefully they'll be effectively on the ropes.

I think civs are usually pretty smart about going to war when they have the lead though. I think they know it's their game to lose. But every once in a while they'll go to war or someone will declare war on them. Then, I become an arms dealer.