It's a great question, but you know, I'm not sure that trying to move in that direction is a role that we would want to take on as a nation in the current environment.
Quite frankly, as abhorrent as nuclear weapons are, their presence has undoubtedly contributed to global security, and for nations that don't have them, that contribution is what they see and why they want them. There's a reason why Korea wants nuclear weapons. There's a reason why Iran would probably like to have them in the fullness of time, because they are an insurance against unwanted attack.
I would love to see the world without them, but I don't see that it is anywhere likely to be something we have in the short term, so why take that on?