I was just reading an article on TV Tropes called Cut Lex Luthor A Check. While reading said article, I came across a great plot for World War III. The war originally grew out of a cold war between the US and China. However, the real reason the war was started was to stimulate the economy and rush development of new technologies. A you play through the game, you see this in effect. Militaries become better-funded, technologies become more advanced and reliable, and later go into civilian use.
I'm not sure how to tell this in-game, though. Maybe you meet the person responsible for starting the war? Maybe it's never actually revealed- just implied.
So yeah. Just quick thought I had. Figured I'd write it down rather than forget it.