The cold war was everything but a war in my opinion. It's was just Threats and a bunch of showing off. It's known as the 'Cold' war because it was a verbal war, and nothing physical, although it could have lead to the end of the world. The united states diplomatically isolated nations that maintain friendly relations with communist states, key word diplomatically, that means nonphysical resolution to conflict. I would go with the last option, it seems to fit best, the other three are absurd.