SEOUL -- U.S. Defense Secretary James Mattis on Thursday kicked off his trip to South Korea and Japan, seeking to reassure American allies in Asia on the country's commitment to opposing nuclear and missile development by North Korea and Chinese maritime expansion.
Mattis promised a stronger alliance with South Korea, saying Washington would stand "shoulder to shoulder" with Seoul in response to the North Korean threat. Most of his meeting time was spent discussing Pyongyang, and he agreed on responding strongly to any new provocations by the North, such as test-launching an intercontinental ballistic missile. This came as a relief to a government in crisis since the impeachment of President Park Geun-hye.
As a candidate, U.S. President Donald Trump had suggested withdrawing American troops from South Korea if the country does not pay more to keep them here. He even hinted at possibly meeting with North Korean leader Kim Jong Un, fueling deep concerns in the South. Mattis did not touch on the cost issue Thursday and stressed the North's nuclear threat as a top security concern for the Trump administration.
By visiting South Korea and Japan rather than the Middle East or Europe on his first trip as defense chief, Mattis demonstrated that he sees stability in Asia as key to U.S. security. He first headed to South Korea to iron out details on the response to the North's nuclear and missile development, a strong signal against provocations by Pyongyang.
North Korea has implied that it is ready to test ICBMs, which could reach the continental U.S. Washington is moving to deploy the Terminal High Altitude Area Defense missile defense system in South Korea. But this has met with harsh criticism from a China seeing THAAD as a threat to its own national security, as well as hesitation from the political opposition in South Korea. Mattis expressed his determination to see the system deployed by the end of the year as planned.
Nicknamed "Mad Dog" Mattis, the former Marine has commanded troops in both Afghanistan and Iraq. He rose to the rank of general and headed the U.S. Central Command, directing forces in the Middle East, before retiring from the military.
With Secretary of State Rex Tillerson a former Exxon Mobil CEO lacking in foreign policy experience, Mattis is expected to take a leading role in Asian diplomacy.
Mattis meets with Japanese Prime Minister Shinzo Abe on Friday to discuss the security environment in East Asia. Tokyo is seeking reassurances that the disputed Senkaku Islands fall under Article 5 of the bilateral security treaty, under which the U.S. would help defend Japan in cases of military attack.
"We trust in U.S. involvement," Japanese Chief Cabinet Secretary Yoshihide Suga told reporters Thursday. "We want to be on the same page with the new Trump administration."
An American commitment to Article 5 will serve as a deterrent against China, which claims the Senkakus for itself as the Diaoyu. Beijing will likely exploit any cracks it sees in the Japan-U.S. alliance.
With Tillerson now confirmed as secretary of state, Japan is working to build a diplomatic and security pipeline to the new administration. The countries' defense chiefs will meet Saturday. Japanese Foreign Minister Fumio Kishida will accompany Abe next week to the U.S., where he could hold his first meeting with Tillerson.