[AmericanInTokyo]

They invariably will turn into roving bands of marauders. Much like armies let go from Central American wars turned into M-13 Mara Salvatrucha gang members, infected Latin America and came up to the USA. Skilled, deadly, hungry, nasty, bad neighbors. Let the raping and pillaging begin, I guess (in the DPRK).

[TigerLikesRooster]

If the unification of Koreas happens, S. Korean military and intel have to absorb (or manage) good portion of these soldiers, missile engineers, nuclear scientists, chemical weapon's experts, cyber-operatives, and security agents.
Otherwise, we have a big nasty organized crime syndicate of E. Asia, which makes Triads, Yankuza, and Russia Mafiya blush. You know NK has already turned into one huge crime-syndicate. If they go free agent, they can go in any direction. They may flood S. Korea or maybe cross Yalu-Tumen River en masse.