Many people claimed that the Soviets could wipe out over 90% of our Minuteman silos in a first strike.
In 1979 a film called first strike was shown to President Carter with an erroneous conclusion.
Obvious propaganda.
I know some of the Navy SLBM engineers, and the deal with the Russians was that they could not miniaturize their rocket and warhead components like the U.S. could, and needed much larger yielding warheads to make sure that their targets were hit during a nuclear war. Their circular error probable (CEP) was measured in miles, whereas ours was measured in yards and feet. Therefore, we could afford to deploy warheads with yields in kiloton ranges (since we could always hit our target precisely), but the Rooskiis needed megaton-range warheads to take out theirs since their accuracy sucked.
And of course in First Strike, Carter surrenders, the cowardly bastard!