I, for one, am not deeply unsettled by nuclear weapons. As weapons of peace, they have made war a strongly negative sum game between advanced nations. The only way to win is not to play. The drawback of nuclear weapons isn't the actual threat or consequences of war, but using the nature of the game by a government to spread fear, uncertainty, and doubt amongst its own people to consolidate power. That, in itself, is…
In theory, yes, MAD and Nash Equilibrium and all that. In practice, people and government are irrational and make mistakes (most notably in 1983 when we almost destroyed the world due to a false alarm) -- and the cost of policing this theoretical balance of power costs a hell of a lot of resources that could be better spent doing more productive things.
I don't think there's more productive use of resources than maintaining peace between big nations.