How does the film Dr. Strangelove suggest that we can't help but laugh in spite that America's stated nuclear weapon policy could kill us all?The...

I would probably distance myself a bit from the wording of
the question.  The film uses humor in a very darkly effective manner.  The nuclear
policy of Mutually Assured Destruction (MAD) is shown to be laughable, but not something
at which to laugh.  I don't think that the film is suggesting that "we cannot help but
laugh."  Rather, I think that the film is bringing to light the flaws in the theory and
thinking that escalated the nuclear arms race to a point where a "Doomsday device" is
present in policies and actions of both nations.  The film creates laughable
governmental officials that are "entrusted" to keep the citizens safe and do everything
but.  The film does an excellent job of satirizing how the policy designed to eliminate
our enemies and make us "safe" can actually result in more disaster than anything else. 
I think that the humor in the film helps to evoke the surreal nature of the modern Cold
War setting.