After President Donald Trump held a summit with North Korean leader Kim Jong-un - a meeting that was by most accounts a dismal failure of strategy- he made a bold declaration that was surprising, even for him.
Experts believe North Korea sees the "denuclearization of the Korean Peninsula" as something that would involve USA or South Korean concessions, including the possible removal of U.S. troops from the Korean Peninsula.
Japanese Chief Cabinet Secretary Yoshihide Suga last week told reporters that the Trump-Kim summit has significantly relieved Japan's security environment, but that the government still plans to go ahead with a plan to install land-based Aegis Ashore missile interceptors.
North Korea remains under strict sanctions imposed in August by the United Nations Security Council that ban exports of coal, iron, lead and seafood - which account for $1 billion of the country's annual $3 billion in trade.
Destroying testing sites is a key first step in denuclearization, as it has a lasting impacting on development capabilities.
Kim is in Beijing on his third visit to China this year, underscoring the major improvement in relations between the communist neighbours.
"These discussions are also ongoing", Mattis said.
In the joint statement, Kim "reaffirmed his firm and unwavering commitment to complete denuclearization of the Korean Peninsula", but made no reference to a timeline. Bob Carlin, a former North Korea intelligence adviser for the State Department North Korea, tells CBS News it is significant that the North is destroying this testing site because it is one of the largest in the country. The violent scenes of American war crimes or crushing U.S. troops are starting to give way to signs that push for the success of an ongoing five-year economic growth plan, reports NK News.
In April 2018, the leaders of North and South Korea met at the demilitarized zone and agreed that by the end of the year the Korean War would be formally ended.
Mr Moon described Mr Kim as forthright, careful and polite.
But it cast no new light on the main question that hangs over the previously reclusive North Korean leader's surge in diplomatic activity in recent months: What next steps, if any, will Mr Kim take to dismantle his country's nuclear programme?
China and the United States both hope to see the Korean peninsula free of nuclear weapons, but Beijing is concerned Washington and Pyongyang might move closer at its expense, a possibility that China sees as threatening to its economic and security interests in the region.
Such temporary reunions are highly emotional as most wishing to take part are elderly people who are eager to see their loved ones before they die.