okay, they're bad.
when Eisenhower first rendezvoused with the aliens, one of the points that the aliens made was for all the nations to destroy their nuclear weapons. Of course the people of earth didn't abide because we still have weapons but they basically told the aliens that it would be stupid to destroy their nuclear weapons with such an unclear future(referring to the aliens and now knowing what technology they posses).
I see the nuclear weapons as a form of interplanetary protection.