I'm pretty sure they'd be nuclear with or without Clinton though. Nuclear weapons are not exactly a big secret anymore, the cat is out of the bag and the tests are only for show, everything can be simulated there is no reason to set anything off.
Bill Clinton (via his emissary Jimmy Carter) cut a deal with North Korea in 1994. North Korea promised to halt nuclear development (but never did) and Clinton gave them more than $4 billion in aid. Essentially, Clinton financed the last part of the puzzle in North Korea's attempt to acquire nuclear weapons.
What it takes to make a nuclear weapon is not hard to find out, true. But the actual skill, technology, and materials to
actually build one is not so easy to come by. North Korea may have become a nuclear power eventually without Clinton's aid but it sure helped accelerate it to the point we are now.
Grant is correct, military action against North Korea is "risking tens of millions of South Korean, Japanese, and American civilians on the west coast to nuclear and chemical attack, and risking war with China." North Korea is reported to have thousands of tons of chemical and biological agents with effective delivery mechanisms. Within hours of hostility, we could easily see entire cities on the Korean peninsula and nearby countries become graveyards as Kim Jong-un is truly threat to use them.
Add in the economic impact of a military effort in Asia. The entire western world depends on goods being built and shipped from Asian countries. This would get severely disrupted for some time and in our "just in time" economy could have far reaching economic implications. After 8 years of malaise in the United States and relatively poor economic growth world wide, I'm not sure we're ready to risk another massive disruption of the scale this could represent.
The only options I see are getting China to force Kim out or some other internal coup. Those a pretty long shot solutions. The time for the Western world to deal with North Korea has passed, no putting this genie back in the bottle.