A woman watches street TV broadcasting breaking news of a North Korean missile launch in Tokyo on April 13, 2023.

A woman watches street TV broadcasting breaking news of a North Korean missile launch in Tokyo on April 13, 2023. KAZUHIRO NOGI/AFP via Getty Images

Missile-defense platform shows warming relations between Japan, S. Korea

By December, INDOPACOM aims to roll out a trilateral data-sharing system prescribed in a May agreement.

SEOUL, South Korea—The U.S., Japan, and South Korea will roll out a platform to share missile threat detection data later this year as part of a broader trilateral agreement designed to bolster security in the region and deter North Korean aggression, defense officials announced on Tuesday.

U.S. Indo-Pacific Command is leading the effort, described as a shared platform to exchange real-time missile warning data to better detect missiles launched by North Korea. The platform is expected to be fully operational in December. 

The effort will be the first time all three countries share information together. The U.S. shared such threat information with South Korea and Japan separately, but historically tense relations prevented collaboration before now, officials said. 

North Korean media has characterized the agreement as “sinister.” It comes amid increasing military cooperation between the three countries, including missile defense drills after North Korea’s test of an intercontinental ballistic missile earlier this year. 

The leaders of each country’s defense department condemned DPRK’s space launch vehicle tests, which are prohibited by the United Nations Security Council Resolutions, according to a readout. 

In August, the White House hosted South Korean President Yoon Suk-yeol and Japanese Prime Minister Kishida at Camp David to commit to expand collaborative research efforts, information sharing and policy coordination, according to the joint statement.

This year marks the 70th anniversary of the U.S.-Korea alliance. The relationship has been strengthened in the past year as the Biden and Yoon administrations have increased bilateral military exercises. 

The trilateral agreement also aims to make cooperative military exercises between the U.S., South Korea, and Japan more regular occurrences, officials said. The countries held a joint aerial exercise in October and a naval exercise in July. Future exercises are expected to be multi-domain, with focuses on maritime and air, defense officials said.