It would be your fault because if you were arrested because you would be breaking Korean law whether you disagree with their laws or not

It'd be your fault. If one enters a boxing match and gets beaten up it's their own fault. That's not to deny the North Koreans' agency but they can't arrest you if you don't go there.

The Left are all about Communism so i think it is a great place for all of them to visit

If you walk onto private property and find yourself paying a consequence, that's on you.

If I went on behalf of a government or institution which was invited in then it would not be. But I'm pretty sure in most cases that hit the news it's because private citizens took it upon themselves to go there with some sort of mission, which ultimately makes it their own fault.

Trust me, if you see on the news that I just got arrested by ISIS in the Middle East then you can be assured that was my own stupid fault. Because I'm not going anywhere near that place voluntarily.

Both. The government chooses to create the laws, and chooses to arrest you. You choose to do the action that the government doesn't like. It's a consequence of both of those things.

Wherever you travel you are bound by the laws of the land. If you do something that is illegal in the country you are in then it would be your fault if you got arrested. It is the travelers responsibility to know about the country they go to.

Those in power get to decide the law.

America doesn't have any power in DPRK.

So, unless that changes any time, you'd be an idiot to even expect them to release you later.

If you consciously stuck your hand into an open fire and got 2nd degree burns, is it your fault, or the fire's fault?