To say that an arms race always leads to war seems to me to be putting the cart before the horse. A government resolved to attain ends detrimental to its neighbours, which does not shrink from the possibility of war, makes preparations for war, its neighbours take defensive action, and you say an arms race is beginning. But this is the symptom of the intention of one government to challenge or destroy its neighbours, not the cause of the conflict. The pace is set by the potential aggressor, and, failing collective action by the rest of the world to resist him, the alternatives are an arms race or surrender.