IRIA News

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The United States, South Korea, and Japan have started a major trilateral military exercise called Freedom Edge, aimed at strengthening coordination in multiple domains against North Korea’s advancing nuclear and missile programs.

The five-day exercise is taking place in international waters off South Korea’s southern island of Jeju from September 15 to 19, according to South Korea’s Joint Chiefs of Staff (JCS). The exercise covers a wide range of joint training, including ballistic missile defense, air defense, medical evacuation, and maritime interdiction operations.

Yang Seung-kwan, spokesperson for the JCS, said the drills were intended to enhance deterrence and improve readiness. “The Freedom Edge exercise is conducted through Friday to strengthen capabilities to deter and respond to North Korea’s evolving nuclear and missile threats,” he told reporters in Seoul.

This round of Freedom Edge is the third trilateral iteration, following previous versions in June and November of last year. It is the first such exercise since U.S. President Donald Trump and South Korean President Lee Jae Myung took office earlier in 2025.

According to the U.S. Indo-Pacific Command, the drills also involve U.S. Marine Corps and Air Force assets and are designed to integrate capabilities across the sea, air, and cyberspace. The command described it as “the most advanced demonstration of trilateral defense cooperation to date.”

South Korea’s Defense Ministry added that the exercise reflects an expanding security partnership among the three countries, particularly in addressing regional threats posed by North Korea’s nuclear and missile developments.

Parallel Iron Mace Exercise

The Freedom Edge drills are taking place alongside Iron Mace, a tabletop exercise between the United States and South Korea. Iron Mace is focused on operational planning and the integration of U.S. nuclear assets with South Korea’s conventional forces as part of extended deterrence against North Korea.

Adm. Paparo 🇺🇸 joined ROK leaders 🇰🇷 in Incheon for the 75th Commemoration of the Incheon Landing.
The anniversary honors the history of the alliance and the shared sacrifice that laid the foundation for today’s partnership. Alongside commemorations, Adm. Paparo met with senior… pic.twitter.com/4acbjoDyxB

— U.S. Indo-Pacific Command (@INDOPACOM) September 14, 2025

While the U.S. and South Korean militaries have not released full details of Iron Mace, South Korean media reported that the exercise explores scenarios in which Washington’s nuclear capabilities would be coordinated with Seoul’s conventional military assets in response to potential North Korean attacks.

North Korea’s Reaction

North Korea has strongly condemned the latest joint exercises. Kim Yo-jong, the influential sister of leader Kim Jong-un, stated that state media was criticizing the trilateral drills. She said, “The reckless show of strength made by them in real action in the vicinity of the DPRK, which is the wrong place, will inevitably bring bad results to themselves.”

She also accused the United States and South Korea of heightening tensions with Iron Mace, warning that such exercises reveal the “confrontational stance” of Washington and Seoul. North Korean state media framed the drills as evidence that the allies intend to escalate military pressure rather than seek dialogue.

North Korea has a history of conducting its own military demonstrations in response to joint drills by the United States, South Korea, and Japan. These have included missile tests, artillery firings, and large-scale exercises of its own forces. Analysts note that Pyongyang uses such responses both to signal defiance and to showcase its advancing weapons capabilities to domestic and foreign audiences.

In the past, calls by Seoul and Washington to resume denuclearization talks have been dismissed by Pyongyang, which has increasingly turned its focus toward strengthening ties with Russia and China. Kim Jong-un’s government has repeatedly declared that it will not abandon its nuclear weapons program, portraying it as essential to regime survival.

The military drills come at a time when North Korea has been deepening its relations with Russia and China. Since the start of Russia’s invasion of Ukraine in 2022, Pyongyang has supplied Moscow with artillery shells, ballistic missiles, and even troops, according to Western intelligence assessments. These supplies have been aimed at helping Russia sustain its warfighting capabilities against Ukraine.

Earlier this month, Kim Jong-un visited China and appeared alongside President Xi Jinping and Russian President Vladimir Putin at a military parade. The joint appearance was seen as a signal of closer alignment among the three countries, each of which has an adversarial relationship with the United States. Observers say the parade underscored Kim’s efforts to secure political backing from Beijing and Moscow while showcasing defiance against Washington and its allies.

Strategic Context

For Washington, Seoul, and Tokyo, the latest drills highlight the growing importance of trilateral security cooperation. The three countries have long conducted bilateral exercises, but trilateral drills have become more frequent in recent years amid concerns over North Korea’s missile launches, China’s regional ambitions, and broader Indo-Pacific security dynamics.

The Freedom Edge exercise follows commitments made at the 2023 Camp David summit, where leaders of the United States, South Korea, and Japan agreed to expand military coordination, intelligence sharing, and missile defense cooperation. Since then, the three countries have intensified their efforts to establish a more integrated defense posture in Northeast Asia.

Despite repeated offers for talks from Washington and Seoul, Pyongyang has maintained a hardline stance. North Korean officials have rejected dialogue on denuclearization, claiming that such talks are a pretext for disarming the country while leaving it vulnerable. Instead, Kim Jong-un has emphasized the expansion of nuclear forces and closer alignment with other U.S. adversaries.

The regime has also sought to highlight its domestic resilience through public displays of military power, framing its weapons programs as a source of national pride and legitimacy. Analysts argue that as long as Pyongyang sees strategic benefit in its nuclear arsenal, prospects for negotiations remain dim.