ROUND 1: South Korea's president meets with North Korea's Kim Jong Un in a historic summit

Reuters

• South Korean President Moon Jae-in met face-to-face with North Korean leader Kim Jong Un in a historic summit in the southern part of the demilitarized zone (DMZ) on Friday.
• The summit marks the first meeting in 11 years for the leaders of South and North Korea.
• The general consenus among the foreign-relations community is that the North-South gathering set the stage for a future conference with US President Donald Trump and Kim Jong Un.

South Korean President Moon Jae-in met face-to-face with North Korean leader Kim Jong Un in a historic summit that has been viewed with both trepidation and optimism. Friday's summit is the latest development in a fast-moving march toward diplomacy on the Korean Peninsula, following what had been a tumultuous 2017 for the region.

Shaking hands in front of a crowd of journalists and photographers, Kim and Moon made history when they greeted each other in what was the first meeting between leaders of the two countries in 11 years.

Moon is the third South Korean president to meet with North Korea's leader. His predecessors, President Kim Dae-jung and Roh Moo-hyun, held smeetings with North Korea in 2000 and 2007, respectively.

Kim and Moon paused for photographs at the concrete steps of the military demarcation line before making their way into South Korea's portion of the Demilitarized Zone (DMZ), where, for the first time since the end of the Korean War in 1953, a North Korean leader crossed the border into the South.

Later in the day, the two leaders are scheduled to plant a commemorative pine tree using soil and water from mountains and rivers in their respective countries, according to South Korea's presidential Blue House.

South Korea Presidential Blue House via AP

The meeting room in which South Korean President Moon Jae-in and North Korean leader Kim Jong Un will meet.

How the two Koreas got here

The journey to the Peace House, the South Korean building where Kim and Moon will convene their meeting, has been fraught with uncertainty, particularly after heightened provocations from North Korea last year. In addition to firing at least 23 missiles in 2017, the regime put its nuclear-weapons progress on full display, testing a miniaturized hydrogen bomb in September that year.

But even as North Korea ratcheted up its missile program, it found a formidable challenge in the US President Donald Trump, who had no apparent qualms about firing equally provocative rhetoric back at the North. Trump frequently threatened "fire and fury" and dropped less-than-subtle hints about US retaliation should the North successfully hit a US target with one of its missiles.

The back-and-forth stoked fears that a conflict on the Korean Peninsula might be brewing.

And the beginning of 2018 looked as though Kim was ready to keep the action going. In his New Year's Day address he declared, "The entire United States is in range of our nuclear weapons, and a nuclear button is always on my desk. This is reality, not a threat."

Government of South Korea via AP

South Korean President Moon Jae-in, center, talks with North Korea's nominal head of state Kim Yong Nam and Kim Yo Jong, right, North Korean leader Kim Jong Un's sister, after a performance of North Korea's Samjiyon Orchestra at National Theater in Seoul, South Korea, February 11, 2018.

The North warms up to its neighbors, and the US

That aggressive posture apparently didn't last. Kim soon dispatched an envoy of North Korean athletes and performers to the 2018 Winter Olympics in Pyeongchang, South Korea. Kim's sister, Kim Yo-jong, also attended and met with Moon during the festivities, delivering a message that eventually paved the way for Friday's summit.

North Korea's conciliatory tone extended beyond its southern neighbor. Following a meeting between South Korean and North Korean intelligence officials in Pyongyang, South Korea delivered a message to the US from Kim: that he would like to meet with Trump.

Trump accepted the request, and preparations for that affair have been underway. Trump, who would be the first sitting US president to meet with a North Korean leader, said that the gathering with Kim could happen in late May or early June. A location hasn't yet been announceed publicly.

In March, Kim also visited and exchanged pleasantries with Chinese President Xi Jinping in Beijing, marking his first meeting with a world leader since he assumed power in 2011.

REUTERS/Jonathan Ernst

President Donald Trump and South Korean President Moon Jae-in shake hands during a meeting at South Korea's presidential Blue House in Seoul, South Korea, November 7, 2017.

Moon and Kim's meeting has critical implications for the future of the Korean Peninsula. North Korea has already made some concessions ahead of the summit - including a declaration that it would stop further missile and nuclear tests and drop its previous demands for US troop withdrawals from the peninsula.

Among some symbolic gestures like bringing a formal end to the Korean War, one of Moon's top priorities will be to reach a consensus on denuclearizing North Korea.

"It's going to take a lot of time and negotiation to see how flexible North Korea will be on this question," Mintaro Oba, a former US State Department diplomat involved in Korean affairs told Business Insider.

"That should be something to probe for after the summit rather than the summit itself. There's many more meetings, many more talks, to find out common ground and see where there can be flexibility."