It's the same situation in Korea, just a different mechanism. The refugee crisis that would result from a DPRK collapse would land on China's doorstep, so the Chinese will do whatever it takes to prevent that from happening. U.S. tourists (or any tourists for that matter) not going to the DPRK won't change that.
What might change the situation is people in the DPRK meeting U.S. tourists and seeing with their own eyes that we are not the monsters we have been made out to be. Big societal changes can grow from small seeds of doubt.
Unfortunately, you can't actually meet DPRK citizens on a tour to the DPRK. The only way you can visit is by going on a DPRK government-sponsored tour where you are herded between 'culturally important' landmarks by government approved tour guides. The DPRK is leaps and bounds ahead of you on controlling this sort of 'cultural creep.' Also, they appreciate the significant donation to their government for the short tour.
> you can't actually meet DPRK citizens on a tour to the DPRK.
Of course you can. Your government minders are DPRK citizens.
> The DPRK is leaps and bounds ahead of you on controlling this sort of 'cultural creep.'
Of course they are. But a tourism embargo is not going to change that.
Look, it's possible that the DPRK really is an evolutionarily stable strategy, and they might be able to maintain their totalitarian regime forever. But if there's a way to crack it, the most likely mechanism is through instilling doubt into individual North Koreans that everything that they are being told is true. The best way to do that is to show them evidence that some of the things that they are being told is not true, and you can't do that if you're not there. You might not be able to do it even if you are there, but at least if you're there, there is a possibility.
