Last night's nigh-historic statement by the South Korean National Security Adviser Chung Eui-yong is another piece of that foundation. You can read the entire statement here, but I'll highlight the important part:
"I told President Trump that in our meeting North Korean leader Kim Jong-un said he is committed to denuclearization. Kim pledged that North Korea will refrain from any further nuclear or missile tests; he understands that the routine joint military exercises between the Republic of Korea and the United States must continue. And he expressed his eagerness to meet President Trump as soon as possible."
"President Trump appreciated the briefing and said he would meet Kim Jong-un by May to achieve permanent denuclearization."
This is the breakthrough that everyone was waiting for. Once Trump gets involved in the negotiations, a deal will be made. That's his wheelhouse, making deals. Everyone walks away a winner in their minds.