If there's anything this crisis has opened me up to, it's for how much the US spends on military advancement and refinement, and is the only country on Earth to have successfully nuked someone, we still haven't created the technology or defense system to invalidate nuclear bombs all these years later.
So some maniac armed with nukes can threaten to blow up D.C. We don't have anything to shoot down or short circuit those nukes out of orbit if they launch, let alone nullify their damage.