Actually, there could be a nuclear war, I remember reading about how nuclear war was closely averted simply because of human errors in judgment thinking war was going to break out, there was some problem with the presidential phones that connect to the other countries.
If there are nukes in the world, people don't want to attack each other (though there is still the aforementioned human error risk). If there aren't nukes, the biggest countries "police" the smaller countries. Read: America vs Iraq. Come to think of it, I reckon America knew Iraq had no WMD's anyway, otherwise they wouldn't have attacked. See: Iran has nuclear weapons and lots of oil, and yet America hasn't gone to war with them.
If there are nukes in the world, people don't want to attack each other (though there is still the aforementioned human error risk). If there aren't nukes, the biggest countries "police" the smaller countries. Read: America vs Iraq. Come to think of it, I reckon America knew Iraq had no WMD's anyway, otherwise they wouldn't have attacked. See: Iran has nuclear weapons and lots of oil, and yet America hasn't gone to war with them.