ITo play Devil's Advocate for a moment, let's assume it doesn't - in 1977 you would have Jimmy Carter and James Callaghan in power in Washington and London. I just wonder if one or both might choose an option other than a nuclear escalation. If France stays out of any conflict and the Russians advance to the Rhine and stop there, what then?
Reagan would be elected in an even bigger landslide, on a platform of "Democrats Threw Europe to the Soviet Wolves". Massive military buildup, saber rattling, probably ends with full-exchange WWIII in the mid-80s.