Might have been NATO on the C64. Nukes usually ended up being thrown around.
Edit: Rummage, rummage, rummage in box of old C64 games. Here it is... NATO Commander.
I loved Red Lightning on the Amiga for a WWIII game. Combat checked to individual vehicle level, an interesting air war and you had to send troops to Iceland & Norway to influence the battle for the Atlantic. I managed to find a download of it for PC too.
SSI did produce some fine games.
I'm currently um-ing and ah-ing over buying Harpoon Commanders Edition from Matrix Games.