I disagree with the 'sideshow' labeling of North Korea.
If we don't stop their plutonium process in the next 3 months they will have mad enough to export untold number of dirty bomb material.
The unrefined plutonium they have in the spent rods is just as dangerous, in terms of a dirty bomb, as refined plutonium. I believe, plutonium is not a good dirty bomb material because it too dangerous to the engineers & deliverers (most poisonous substance known to exist), too radioactive (detectable), too unstable (
burns when exposed to air) and finally, because it is a synthetic element, too expensive (worth thousands upon thousands perhaps millions of times it weight in gold, most valuable).
The only value obtained by refining the spent rods is to create a nuke because you need purity to sustain a chain reaction.