This did not go over well with the Trump administration. Ultimately the threat of war with North Korea was too dangerous and ran the risk of losing a bigger war with China if things turned ugly as well as the high possibility of North Korea quickly retaliating against South Korea and millions dead very quickly.
Thus the summit. Trump would have liked to present a first strike scenario whereby we came into North Korea militarily and took out all nuclear weapons capabilities right now but the costs were just too high. This was all calculated by North Korea and probably more specifically by China years ago as they set up North Korea as a blackmail tool against America.
So when Trump decided that option was unworkable and China was coaching Kim Jong Un attempting to be in the driver's seat when it comes to the future of North Korea, things did not go over well at all.
Almost immediately afterwards the Trump administration readied a new round of tariffs against China followed by retaliatory measures by China and now another new and bigger round of tariffs from Washington coming soon. All of this points to the Trump administration saying we won't invade North Korea but we are going to play hardball on trade until we get the outcome we want on both North Korea and everything else including Taiwan, the South China Sea and international waters, etc. Both sides are now playing the long game with all of these issues in mind at every turn for the 21st century geopolitical chessboard.