Imagine there are three people in a room and each person is pointing a gun at the other two people. Anybody can chose to fire their weapon at any time, but they cannot actually hit and disable the other two before those parties get a shot off. If the participants are rational then a stable equilibrium exists. Nobody will fire. Next, it is proposed that three parties put their loaded guns on a table a few steps away and then return to the original position of facing each other. None of the parties is now sure of who could get to the guns and get a shot off first. That is not a stable equilibrium.
A push for total global nuclear disarmament is discussed in the Economist this week. This strikes me as incredibly naive, especially for the usually level headed Economist. The suggestion is that we move from an equilibrium of mutually assured destruction to an unstable situation where nuclear weapons don’t exist but can be produced in a short period of time. It is just a dumb idea. How would any of the existing powers convince themselves that the others were not secretly harbouring weapons that were ready for launch? Facing that concern every power would secretly store weapons and we would go from a world where the weapons are out in the open, to where they are hidden.
Extending the analogy above the supporters of total nuclear disarmament, say that we are about to go to a world where instead of three people pointing guns at each other we will have 15 people pointing guns at each other, and not all of them will be thinking rationally. Maybe so, but is the US disarming itself going to make North Korea less likely or more likely to use nuclear weapons?