Geoff, old bean, you are correct. Developing a nuclear weapons program for your country is quite rational. Every country that has nuclear weapons is treated differently than those that do not -- and usually to their political power advantage.

Moreover, the "dictators and assorted fruitbats" -- thanks Mac -- aren't necessarily irrational when they behave as brutal thugs. Some degree of paranoia is rational when you are running a dictatorship -- Stalin's model works smoothly if you set aside the evil thing.