Yes, NATO could make a difference in a conventional war, but the war could all too easily go nuclear.

When you talk about sitting and waiting if there is a nuclear attack, I think you are assuming that you will be in the epicenter of the strike, where instant death is guaranteed. That might be true, depending of course on where you live. But anyone on the edges is left in a terrible situation, facing a probable slow death by radiation sickness with little support from a society left in ruins. That's not even to mention the effects of a nuclear winter.

The avoidance of nuclear war should be the absolute number one priority in all of this.