Mattis to re-assure Japan, South Korea that Trump won't bite

President Donald Trump (L) and Defense Secretary Gen. James Mattis watch the Inaugural Parade from the main reviewing stand in front of the White House on January 20, 2017 in Washington, DC.
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U.S. Defense Secretary James Mattis will wrap up talks in South Korea before traveling to Japan later on Friday, as he reminds both countries of Washington's support amid uncertainties over President Donald Trump's policies, a belligerent North Korea and China's territorial ambitions.

It is the first international trip among Trump's cabinet secretaries, according to Reuters, underscoring the importance Trump places on Seoul and Tokyo while he threatens a trade war against Beijing, experts said. The visit should also allay broad concerns about American leadership in Asia and fears over the future of South Korea and Japan's bilateral relationships with the U.S.

"The message of this trip is reassurance; reassurance that the Trump administration recognizes the importance of alliances with South Korea and Japan as well as the seriousness of the security situation there," explained Kathleen Stephens, American ambassador to South Korea from 2008-2011.

During his election campaign, Trump pledged to remove existing American troops from Asia if host nations did not pay 100 percent of the costs—a troubling thought for Seoul and Tokyo, given that defense is a key priority in their respective relationships with Washington. Around 28,000 American soldiers are currently stationed in South Korea, while 54,000 U.S. military personnel are based in Japan.

North Korea top priority in Seoul

North Korea, a common thorn in the sides of Washington, Seoul, and Tokyo, featured prominently in Mattis' talks with top South Korean officials on Thursday. The retired Marine Corps general said that his country would stand "shoulder-to-shoulder" with Seoul to face the North Korean nuclear threat, Reuters reported.

Pyongyang has been increasingly hinting that it is ready to test an intercontinental ballistic missile (ICBM), adding to rising fears it will act on threats of targeting enemies with a nuclear weapon. Choe Kang II, deputy director general for North American affairs at North Korea's foreign ministry told NBC News on Jan. 25 that Pyongyang was ready to test an ICBM "at any time, any place," That same day, Mattis' predecessor Ash Carter warned Washington would shoot down any missile aimed at it or an ally.

North Korean leader Kim Jong Un's nuclear program is a matter crucial to Trump's re-election so Mattis will likely look to discuss ways to disarm the rogue nation as well as deploying preventative measures against potential attacks, said Christopher Hill, former U.S. ambassador to South Korea from 2004-2005.

In July, then South Korean President Park Geun-hye agreed to host a American defense technology system called Terminal High Altitude Area Defense (THAAD), which is designed to shoot down ballistic missiles. But the current political turmoil in Seoul could endanger THAAD implementation.

In the aftermath of Park's resignation, the country is due to elect a new leader later this year and leftist opposition candidates are increasingly seen as the likely winners. It's not yet clear whether these leftist parties will support THAAD or give into Chinese pressure to ditch the system, remarked Hill.

China and Russia believe THAAD deployment on the Korean Peninsula will threaten the mainland's national security interests. "No other nation" should be concerned about THAAD," Mattis said on Thursday, according to Reuters. "Were it not for the provocative behavior of North Korea, we would have no need for THAAD out here," he added.

Hill, who led a series of negotiations aimed at halting Pyongyang's nuclear program known as the Six Party Talks, believes Kim's regime is entirely capable of developing a weapon that can reach the U.S. within the next four years. Coinciding with Matthis' arrival in Seoul on Thursday, the White House will be launching a review of its North Korea policy, the Financial Times reported, citing unnamed sources.

Because Kim has expressed zero interest in denuclearization, Mattis has little chance of resuming multi-nation talks, Hill noted, adding that the best option for Trump is to slow the pariah state's nuclear program, which can't be done without Beijing's help. But that may prove to be tricky amid worsening U.S.-Chinese ties. In a tweet last month, Trump criticized China, a traditional ally of Pyongyang, for its lack of assistance on the nuclear issue.

Trump trying to reassure S.Korea: Former ambasasdor
Trump trying to reassure S.Korea: Former ambasasdor

For Tokyo, China tensions and trade are key

Japan's territorial dispute with China in the East China Sea could be key topic when Mattis meets Japanese Defense Minister Tomomi Inada on Friday. A group of island known as the Senkaku in Japan and the Diaoyu in China have been a source of conflict between the two Asian heavyweights for years, with Tokyo repeatedly urging Beijing to halt construction activity in the area.

"Mattis will supposedly reassure the Japanese that not only will the U.S. continue the security treaty, but that issues like the disputed Senkaku-Diaoyu islands will still fall under the treaty," said Rodger Baker, vice president of strategic intelligence at Stratfor.

Despite lingering uncertainties about Trump's policies, Japan has been especially keen to gain his favor. In fact, Prime Minister Shinzo Abe was the first foreign leader to meet the Republican when he was still president-elect and another summit is scheduled for Feb. 10.

"Mattis' visit is another opportunity for the Japanese to state their case why they are America's strongest ally economically, politically and security-wise in the region," Baker noted.

The South China Sea, a hotbed of geopolitical tensions between Southeast Asian governments and Beijing, could be another topic of discussion.

Last month, Trump's White House promised to defend American interests in the disputed region, marking a sharp turn from the previous caution exercised by U.S. leaders. Beijing then responded saying it possessed "irrefutable" sovereignty over the resource-rich area.

"The U.S. is interested in maintaining the rite of passage in that area. But China wants to establish a precedent over time where they control those waters," explained Bruce Bennett, senior defense analyst at RAND. "The U.S. needs to break that precedent now. That doesn't mean going to war but it means making it clear that international law should apply."

In July, Beijing rejected a ruling by The Hague's Permanent Court of Arbitration that said China's claim to the 1.4 million-square-mile body of water was not valid.

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