While those deals didn't work out, we find ourselves in a promising situation now. Let's focus on the here and now, the Panmunjom Declaration. How significant is it? And, more importantly, is it finally going to break the cycle of failure?

Since Kim Jong-un's New Year's address, Pyongyang has expressed its hopes to denuclearize a number of times,… but the Panmunjom Declaration was the first time Pyongyang actually stated that in a document. Some experts also say that it was significant to have Kim read out the declaration side by side with President Moon Jae-in,... and that this was broadcast live around the world. So they are quite optimistic for a real breakthrough this time around.

"It was announced like it was a promise to the world. The mention of 'complete denuclearization' can be seen as a comprehensive description of what South Korea and the U.S. have been asking for -- 'complete, verifiable, irreversible' denuclearization. I think the two Koreas have now set some common ground on the issue."

And some experts also point out how the North wants South Korea to play a role in its denuclearization deal this time, unlike before where it only sought to have direct talks with the U.S. So the experts say that South Korea's role as a mediator could be something different that could make this work.

"The Panmunjom Declaration stipulates that South Korea will play its 'respective role and responsibilities' in denuclearizing the North, and I see this as a promise to become the witness for both the North and the world. It shows that South Korea guarantees North Korea's willingness to keep its promise to denuclearize,... as well as guaranteeing the world's support and trust in Pyongyang."