The disarmament of rival nations can only take place when all countrie
s involved are made better off and a feasibility criterion is also sat
isfied. Disarmament is more probable when nations face a similar trade
off in the acquisition of weapons, when developments in military capa
bilities can be speedily and accurately verified, and when the existin
g weapon systems are easily reproducible. A successful disarmament als
o requires that the speed of the disposition of arms be neither too fa
st nor too slow.