As South Korean President Moon Jae-in gears up for a June 29–30 summit with Donald Trump, his ardent desire is to engage North Korea and revive the “sunshine” policies of his progressive predecessors, Kim Dae-jung and Roh Moo-hyun, could be a major source of friction. This sentiment comes at a moment when the United States and the international community are seeking to toughen UN National Security Council sanctions and put maximum pressure on Pyongyang.