I have quite limited knowledge on the NK/SK/China/USA intricacies but is there a possibility that pending a civil war that (assuming KJU's death and a lack of direct successor), to protect S.Korea and more importantly to distract from Trump's terrible current image and as a push for re-election could the USA attempt to invade NK under the guise of peacekeeping. Conflicting this with the idea that China requires a buffer zone between the US/S.Korea (is this what happened during the Korean war in the 50s?) Could North Korea become another proxy war between America and China through the guise of NK/SK?
edit: Aren't they still technically still at war over this exact issue today?
Technically, yes, but no sane person wants it to become an actual war again. It wouldn't work as a proxy war, really, as you'd almost certainly end up with USA soldiers and Chinese soldiers fighting each other directly. It would be too blatant to be a proxy. It would also be a bad fit for a domestic image-boosting exercise because the death toll would be very high even if it didn't go to full on NBC WMD slaughter (which it might - North Korea has all three and China and USA have nukes, lots of nukes). Also, a part of Trump's vote-winning image was to take the USA out of wars, not put the USA into wars. Hence, for example, screwing the Kurds over in Syria by withdrawing USA troops from there.