Are there bad prisons in the US? No doubt. Is the average US inmate experience anything like what is the RULE in these gulags? No. Does the scale between the two matter? Yes. Do the crimes (sometimes "crimes") and due process issues matter? Yes. Can we go on and on with specific, provable differences which make the NK citizen's experience far more horrifying? Yes.
Problems with the prison system in the US belong in their OWN THREAD, where they don't distract from THIS PROBLEM. The fact that some folks feel the overwhelming urge to bring them up here speaks a lot about what they think is important: Scoring points against the US. The US prison system is not relevant to the NK prison system. This isn't a game. NK doesn't get to pick out worst case practices from the US to justify its sweeping unchecked abuses. And it certainly doesn't deserve the aid of willing amateur PR people on random internet message boards.
NK is the same country that quietly let millions of its people starve while it spent a large fraction of its total wealth trying to build the tallest hotel in the world! That's the philosophy and those are the priorities of the organization behind these gulags. But you're telling me the REAL story here is the US prison system?
But this is why NK gets to go merrily about its way starving and torturing its citizens.