Dr K has an insightful point:
A better formulation [in sending a message to North Korea] would be the following: 'Given the fact that there is no other nuclear power so recklessly in violation of its nuclear obligations, it shall be the policy of this nation to regard any detonation of a nuclear explosive on the United States or its allies as an attack by North Korea on the United States requiring a full retaliatory response upon North Korea.'
This is how you keep Kim Jong Il from proliferating. Make him understand that his survival would be hostage to the actions of whatever terrorist group he sold his weapons to. Any terrorist detonation would be assumed to have his address on it. The United States would then return postage. Automaticity of this kind concentrates the mind.
This policy has a hitch, however. It works only in a world where there is but a single rogue nuclear state. Once that club expands to two, the policy evaporates, because a nuclear terror attack would no longer have a single automatic return address. Which is another reason why keeping Iran from going nuclear is so important. With North Korea there is no going back. But Iran is not there yet. One rogue country is tolerable because it can be held accountable. Two rogue countries guarantees undeterrable and therefore inevitable nuclear terrorism."
But there's another hitch, as well, I suspect. What about Pakistan? I fear that there are elements within the Pakistani government and intelligence services that would be only too willing to hand over nuclear wepaonry to Islamist terrorists. And Musharraf's hold on power is tenuous.