[credit_guy]

> Therefore: "use it or lose it".

Not really. It's more like "don't use it so you can lose it". The US has enough SLBMs that the ICBMs can all be lost without significant loss of deterrence capability. However their existence complicates tremendously the calculus of an adversary. If the US does not use its ICBMs in the early moves of a full-scale nuclear war, its adversaries need to allocate missiles to disable them. From wikipedia [1]:

  > The solid fueled LGM-30 series Minuteman I, II, III, and Peacekeeper ICBM configurations consist of one LCC (launch control center) that controls ten LFs (launch facilities) (1 × 10). Five LCCs and their fifty associated LFs make up a squadron. Three squadrons make up a wing. Measures were taken such that if any one LCC was disabled, a separate LCC within the squadron would take control of its ten ICBMs.

  > The LGM-30 LFs  and LCCs  are separated by several miles, connected only electronically. This distance ensures that a nuclear attack could only disable a very small number of ICBMs, leaving the rest capable of being launched immediately. 

That is actually the reason the land-based ICBMs of the US are not MIRV'ed: in order to take them out you need to spend at least one warhead to take out one warhead.

The US nuclear strategists have given a name to this: the "nuclear sponge". Most certainly the options given to the President account for this. Nobody without top secret security clearance can know, including the book's author, but it's highly unlikely that a pre-scripted nuclear counterattack of the US against a single NK ICBM would remove 50 missiles from this "sponge", when a much better alternative is to use SLBMs.

[1] https://en.wikipedia.org/wiki/Missile_launch_facility#Minute...