NEW YORK -- The historic summit between President Trump and North Korean leader Kim Jong Un resulted in an understanding that Pyongyang would work toward denuclearization. The U.S. would also stop joint military exercises in South Korea.

Now that the summit is over, Secretary of State Mike Pompeo is busy working on implementing the summit's agenda. "Face the Nation" moderator Margaret Brennan reports Pompeo will go to South Korea and China to speak to officials about their roles in making sure North Korea follows through on their promises. Pompeo and national security adviser John Bolton will also meet with the North Koreans next week to work on the details.

President Trump (3rd R) shakes hands with North Korean leader Kim Jong Un (3rd L) as they sit down with their respective delegations for the U.S.-North Korea summit at the Capella Hotel on Sentosa island in Singapore on Tue., June 12, 2018. Getty

Despite the uncertainty, CBS News senior security contributor Michael Morell, former acting director of the CIA, says the meeting should be considered a success.

"It was a diplomatic win, because It was the best possible outcome of the summit," Morell said. "Shared objectives to denuclearize and an agreement to continue the negotiations."

But Morell says the U.S. is far from being able to claim a strategic victory, given the "immense details to work through."

For example, before the summit with Kim, Mr. Trump withdrew from the Iran nuclear deal, saying it wasn't strong enough. But as Brennan explained, Iran did not have a nuclear weapon when it agreed to freeze its nuclear development and ship out 97 percent of its enriched material.

"North Korea already has usable nuclear material," Brennan said. "They have the delivery mechanisms, they have the ballistic missiles. They have also claimed to have tested a hydrogen bomb more powerful than the one that was used in Hiroshima. So there's a big unknown for U.S. intelligence here, which is still, while they believe they have the ability to deliver, and they have nuclear material, can they actually successfully launch a weapon? And that's why inspectors need to get on the ground."