[Feniks]

Not really true. Thanks to advances in technology POTUS had 10 minutes to launch by the 1970s before Washington was toast.

It was an open secret that nuclear retaliation could be instigated without White House or even Pentagon approval if the Soviets tried to decapitate Nato.

[lsc]

"Of course, the whole point of a Doomsday Machine is lost if you KEEP IT A SECRET!"

A rational player would only put effort into a retaliatory strike capability to the extent that actually having a retaliatory strike capability strengthened the enemy's perception that they would be obliterated if they struck first.