[Tallguy]

After all, there are plenty of stolen designs from the 1990's to test out and sales demos to conduct.

Designs are one thing. Being able to manufacture it to spec, then assembling it properly are 2 other factors.

You may be right (that this is a physically small warhead, small enough to fit a Taepo-Dong 2), but I tend to believe that the easiers bomb to manufacture (for a first-timer) is still 4X to heavy for that missile to loft.

[NonValueAdded]

But we tend to assume everyone is starting from scratch, from the top of the same learning curve. That is a critically flawed assumption to make! I realize life is not a Clancy novel but that's not to say there wasn't a firm technical underpinning to Clancy's nuclear yarn. Precision machining equipment (along with everything else) has advanced an incredible amount since Fat Man and Little Boy. Add that fact that our national laboratories have been leaking like a sieve and my conjecture is not implausible.

There are lots of reasons to discount the threat as not imminent, like your other point to me that targeting a carrier group is not an easy thing. True, but IMHO there's a lot of puckering going on as the number of years before we really gave to worry has shortened considerably. There is no joy to be had.