"Let;s get a little wager going, I put $20 on Iran is next."
That's a good bet. However, Iran only has one thing we need and do not need more of; oil. We own Iraq for now, remember?
As for North Korea, they dare not wave the nuclear card. China, and soon, Japan, will be the first to dim their flame.
North Korea has no exports, and therefore no bargaining power.
Good luck with your usual threats, Ping Pong. The world really doesn't care.