The Realm of Plausibilty and the Not-So-Plausible

I had an interesting idea of trying to make this last story go nuclear, but I'm not sure if I'd be drifting away from the plausible and onto something thats completely in the realm of fantasy, although who doesn't love an atomic weapon in a story?  I was shooting for realistic, but I didn't want to make it completely off the wall.  I did manage to scrap some cool little plot twists so far, and I think I am going to make my story take place in the 80s instead of the present.  Its gonna give me some ideas that'll will fit with what I want to accomplish, but I'm a little hampered since its a slightly less advanced age I'm dealing with.  I'm off to a good start though.  I'm three paragraphs in, and its going ok far.  I'm not too stressed out about the start of this, and that's not often the case.  I usually freak out, and panic out things.  There's a shot I might have a good story to write for a change.  Gotta love that, right?