Explanation: During the Cold War, a number of wartime scenarios were planned for by the military staff of both sides of the conflict. In most scenarios, Soviet-aligned forces would push through NATO-aligned forces at the Fulda Gap, through NATO-aligned West Germany. Where the plans went from there... varied.
France, which had an independent nuclear arm and policy, regarded its best defense against this possibility by...
... nuking West Germany as soon as Soviet troops came through.
No more Soviet invasion AND no more Germany? The French saw no downside!