Our military power is our gurantee we remain #1 or we take the world down with us. i would strike rational behavior out of all equations myself.
Our military power ain't what it used to be. Against any one country? We win. Against the combined efforts of Russia, China, India, Iran and others? What are we going to do? Nuke all the submarines of Russia, China, India and Iran in a pre-emptive strike. Its not as if the French and Germans are going to follow us into war with the Russians and the Chinese.