Blert is correct that a sea-launched ballistic missile (SLBM) has been a counter-value weapon and was too inaccurate for counter-value use against missile silos. That’s been upgraded now I’m sure. Russian bombers would likely be already in the air and not much threat anyway.

A typical boomer had 10 missiles with 3 warheads each or 30 warheads. Each warhead was 100 kT or so (I forget the exact numbers) each big enough to level a good sized city. The Soviet Union had about that number of good sized cities. Hence only one boomer was capable of destroying almost all the metropolitan areas of the country. I did a calc like this for a NROTC class I took in college – it was a substitute to a phys ed requirement I would have had to take in Florida over the summer!

As to the short and intermediate term effects of a full nuclear exchange in the late 50s or 60s, you have to remember that a large part of the US force was 25 MT SAC gravity bombs or Titan II missile warheads, most intended for ground burst. Such an event would leave a fallout pattern that would be lethal over an area of 100 miles by 25 miles for a 24 hour exposure. You couldn’t walk out in time.

The Cuban missiles were indeed countervalue weapons with little tactical utility. I remember the drills as a kid on the Florida gulf coast and how the school sent home offers to sell dog tags for the children so that the parents could identify the bodies.

There was always something sobering in realizing that the largest country on the planet was spending a big chunk of its national resources on weapons designed specifically to kill you and your family and friends.