Nuclear weapons, like guns and cars, are just tools, and themselves not inherently evil. Ergo, there should be no restrictions on anything related to nuclear weapons.
True!
http://en.wikipedia.org/wiki/Peaceful_nuclear_explosions#Sov... / http://en.wikipedia.org/wiki/Operation_Plowshare
Beyond the obvious (digging big holes fast) there are proposals for using them to extinguish particularly bad oil/gas fires (perhaps Centralia, Pennsylvania could be a use case?), stimulating natural gas production (this one is likely to be unpopular these days), and destroying large amounts of chemical weapons (and while you're at it, a nuke ;)).
Guns don't cause crime, cars don't cause accidents, and nuclear weapons don't kill people: their (usually) negligent operators do.