The nuclear arsenal is for Russia and China and self-defense, it's useless in WW3 unless mutual assured end-of-civilization is desired (or as a one-off response to someone like Iran or Pakistan using a nuke or a small number of them). That arsenal is no more risky in the US hands than in, say, the hands of Russia or China or Britain or France.

The military industrial complex wants money and power, not global annihilation - always remember it's run by people, and they want what most people in power want. It's not a complicated beast, it's mostly about the world's largest slush fund, $700 some odd billion up for grabs every year, and they want all of it and more if they can get it. The military people want to play military, and the industrial people want to play industry, and they leverage each other to that end.

Yes, I think they'll force more wars. Something that big and powerful, in a state of desperation for survival, is scary indeed. I think that's what the play in the 'sandbox' (the middle east, aka where you can launch wars and suffer no domestic enemy retaliation and you can't hardly 'lose' in a classic historical sense) has been largely about, excuses to spend large amounts of money and build & experiment with shiny new war machines. If it had been about economics, oil for example, we'd already control most of the oil in the middle east (we'd have taken Saudi Arabia and Iraq's oil through force). I think that explains Wesley Clark's shocking admission about the Pentagon planning all the wars far in advance:

http://www.youtube.com/watch?v=bSL3JqorkdU