These young agitators were able quicklyamass themselves in new locations because they were spreading the word about attacks through Facebook, Twitter and (especially) the encrypted messaging system offered by BlackBerrys.
Under federal law, there is no limit to how many handguns or assault weapons a purchaser can buy at a time, allowing gun traffickers to quicklyamass guns suitable for an army.
North Korea could certainly quicklyamass enough plutonium for five or six more bombs (to add to the couple it may already have), or it could sell some plutonium to proliferators elsewhere.