I would be a little reluctant to uptalk America's role in this situation, Trump in particular. Much of this has happened independent of the United States, and because of China's influence in the region. If anything, his efforts have further alienated our allies and driven them more into the arms of their neighbors and other trade partners and away from American influence (Mexico and Canada bypassing the United States to make deals in Europe and Asia is a fine example). It definitely appears that they are intent on replacing the United States with other customers who are willing to play a little nicer (maybe China has convinced NK that they can benefit from this situation). Although, Trump's unpredictable behavior may have given North Korea pause and a reason to play a little nicer. It still seems more likely that this is political and economic maneuvering and they will either use America's unwillingness to cooperate as a wedge to drive between allies, or they will play up to Trump's ego and tensions will ease (giving Trump an opportunity to claim a win, even if little of it can be attributed to him personally).
Well this is quite a shock. I wasn’t expecting it to happen. After 65 years and a dictatorship still in North Korea, it ends just like that?
Kim Jong-un is a western educated man who has experience living in Europe and writes/speaks English. It's just my opinion, but I always figured that after he secured enough power and was in a good enough position he would open up to the world more than his father. The fact that China has made a lot of head-room with them in the last couple years has probably helped it along, especially given currently Asia/U.S. tensions. This also isn't an end to the mess, it's an agreement to engage and cooperate, it's ground work, but not an actual peace treaty or trade deal, but it's definitely a good start.