Mutually assured destruction

Mutually assured destruction was a state of being or military tactic during the Cold War. It meant, according to Lieutenant Stepashin, that both parties to a conflict had enough power to obliterate the other, allowing for an uneasy peace. The Eleventh Doctor created such a state of affairs between himself and Skaldak. The Ice Warrior threatened to launch a Soviet submarine's nuclear missiles, while the Doctor threatened to blow up the submarine with his sonic screwdriver. (TV: Cold War)

In 1958, the Tenth Doctor assured American Cassie Rice that the Russians were as scared of nuclear war as she was. (TV: Dreamland)