Imagine this: The U.S. and DPRK delegations go into a new round of denuclearization talks. They can't agree on the trade-off: Sanction relief in return for giving up nukes. Would you be surprised? No, probably not.

What happened in Hanoi and Singapore is basically that, the only difference is that the chief negotiators are the president of the U.S. and the top leader of the DPRK. We assumed the negotiation between the two heads of state would be different, but we were wrong.

There is a reason why the Americans and the Koreans have not reached an agreement for decades. The issue is complicated, extremely complicated. Both sides have too much at stake and not enough trust. Normally a bottom-up process is the normal approach to limit differences and build trust.

But President Trump and Chairman Kim saw a chance to do it top-down.

It makes sense, as all the important decisions should be made by the top leaders. We should applaud them for their vision and courage. But obviously they are blindsided this time by too much confidence and a lack of preparation.

As for the denuclearization itself, yes, there are some cracks, but diplomacy hasn't melted down. The prize is big, it takes concessions and it takes time.

President Trump and Chairman Kim have made differences, we have seen a freeze in nuclear and missile tests from the north and a halt in the U.S.' war games with the south.

But for both leaders, it is a moment of critical choices. Mr. Kim needs to make good on promises to nurture the economy and ensure his country's survival, while Mr. Trump faces the biggest opportunity of his presidency for a diplomatic breakthrough.

According to the New York Times, when Kim met Mike Pompeo in Pyongyang, Kim said, “I'm a father and a husband. And I don't want my children to carry the nuclear weapons their whole life.” President Trump heard those words too.

A top-down negotiation is a high-risk high-return process. What we saw in Hanoi is the risk part, but it is not the end of the game. Trump and Kim just need to finish what they have started.

George Marshall once said conducting war is simple because one knows the objective. To make peace is not. Let us hope both the Americans and Koreans know what they really want.

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