This is what the non-proliferation treaty is for. Smaller countries could already do this if they want, as they aren’t treaty limited in terms of the number of weapons they make, but getting themselves down the cost curve wouldn’t make export profitable or desirable because they have to eat the cost of going down the cost curve in the first place and no one that would only buy cheap nukes is going to compensate them for this. Depending on how much data North Korea got from prior tests, they might still require a lot more testing, and they certainly require a lot more nuclear material which they can’t get cheaply. Burning more of their economy to get down the cost curve isn’t going to enable them to export profitably, and if they even started it could be the end of the regime (due to overmatch by U.S. + Korea + Japan). The “profit” they get from nukes is in terms of regime security and negotiating power… they aren’t going to throw those in the trash. They might send scientists, but they aren’t going to give away free nukes, or no one is going to let planes or ships leave their country without inspection for years. The Cuban missile crisis was scary for the U.S. and USSR, but a small state making this sort of move against the interest of superpowers is far more likely to invite an extreme response (IMO).
This is what the non-proliferation treaty is for. Smaller countries could already do this if they want, as they aren’t treaty limited in terms of the number of weapons they make, but getting themselves down the cost curve wouldn’t make export profitable or desirable because they have to eat the cost of going down the cost curve in the first place and no one that would only buy cheap nukes is going to compensate them for this. Depending on how much data North Korea got from prior tests, they might still require a lot more testing, and they certainly require a lot more nuclear material which they can’t get cheaply. Burning more of their economy to get down the cost curve isn’t going to enable them to export profitably, and if they even started it could be the end of the regime (due to overmatch by U.S. + Korea + Japan). The “profit” they get from nukes is in terms of regime security and negotiating power… they aren’t going to throw those in the trash. They might send scientists, but they aren’t going to give away free nukes, or no one is going to let planes or ships leave their country without inspection for years. The Cuban missile crisis was scary for the U.S. and USSR, but a small state making this sort of move against the interest of superpowers is far more likely to invite an extreme response (IMO).