File photo shows U.S. President Donald Trump. (Getty/Kyodo)

WASHINGTON - U.S. President Donald Trump is willing to work with new Japanese Prime Minister Yoshihide Suga to enhance the bilateral relationship that has grown stronger during the long tenure of Suga's predecessor Shinzo Abe, the White House said Wednesday.

"President Donald J. Trump is ready to continue pursuing the vision of a free and open Indo-Pacific that he and former Prime Minister Shinzo Abe forged, including by further strengthening the U.S.-Japan alliance and advancing our shared goals," the White House said in a statement, referring to a concept that has evolved amid China's growing assertiveness in the region.

"The relationship between the United States and Japan has never been stronger, and President Trump looks forward to working with Prime Minister Suga to make it even stronger," it said.

Suga, 71, a longtime Abe loyalist, has vowed to carry on his predecessor's foreign policy, saying that the alliance with the United States will remain the cornerstone of Japan's diplomacy and security, as the nation also works with its neighboring countries.

Japan's new Prime Minister Yoshihide Suga speaks at a press conference at his office in Tokyo on Sept. 16, 2020. (Kyodo)

Some experts on Japanese politics and security issues in the United States pointed to concerns as to whether Suga, who has served as chief Cabinet secretary under Abe for nearly eight years, can deliver a stable government, while raising questions over his selecting for defense minister an official they view as a relative "novice" in the area.

"There's a lot of anxiety in transitioning from the longest government that Japan has ever seen, a uniquely stable government, particularly in a very unstable moment," said Tobias Harris, an analyst in Washington at consulting firm Teneo Intelligence, during an event hosted by the Heritage Foundation, a Washington think tank.

Over the past years, U.S.-Japan relations have been tested through the administration of Trump, who has asserted his "America First" unilateralist agenda and pressured allies, including Japan, to pay a larger share of the cost of hosting U.S. forces.

At the same time, Japan's security environment has remained severe in the face of North Korea's nuclear and missile threats as well as China's maritime assertiveness in the East China Sea, where the Japan-controlled Senkaku Islands, also claimed by Beijing, are located.

While Suga has been constantly in the public eye, holding twice-daily press conferences as the top government spokesman, his diplomatic skills are yet to be seen.

He is "still something of an unknown figure and so I think that alone created a lot of anxiety that people are trying to fill," Harris said.

Suga took over Abe's position as the ruling Liberal Democratic Party president by winning the leadership race on Monday and was elected prime minister in parliament on Wednesday. He is entitled to serve the remainder of Abe's three-year term as LDP president through next September.

But to hold on to power longer, he has to win the next party leadership race while winning parliamentary elections -- the most imminent one being the House of Representatives election that must be held by October next year.

Harris said Suga has "a good chance" to survive beyond next year, with some polls suggesting that many in the public are hoping for political stability in the wake of Abe's abrupt departure and opposition parties remaining weak.

Jeffrey Hornung, a political scientist at the Rand Corporation, a U.S. research organization, said he thought the appointment of Nobuo Kishi, a 61-year-old younger brother of Abe, as defense minister suggested that the Suga government is not necessarily planning to make any bold decisions on security issues in the near future.

Kishi has served as a parliamentary vice defense minister in the past, but he has not been actively expressing his views on security issues in public.

Japan's new Defense Minister Nobuo Kishi. (Kyodo)

"There are plenty of defense policy wonks in the LDP that could have taken on that role, and for me when I see that he put a novice for the defense minister, that tells me that Suga's not really thinking about prioritizing security issues, at least until the next election or at least until he reshuffles the Cabinet," he said at the same think-tank event.

"Even with his background, his experience with dealing with defense issues is limited," Hornung added after the event.

Abe, 65, who decided to step down due to a chronic illness, has been hailed in the United States for strengthening the alliance such as by pushing ahead with new security legislation that expanded the role of the Japanese defense forces overseas despite public outcry that it would erode the country's postwar pacifism.

Abe has also encouraged the next government to continue discussions on whether to acquire so-called strike capabilities against ballistic missile attacks from an adversary's territory, another sensitive issue in light of the war-renouncing Constitution.

"If Mr. Suga was serious about really moving forward with strike capabilities, then I would have expected to see somebody who's really deep in defense issues because they're going to have to be up there in the Diet and be defending that and explaining it to the public," Hornung said.

Suga also needs to work to forge ties with 74-year-old Trump at least until the U.S. presidential election on Nov. 3, in which the Republican incumbent faces Democratic presidential nominee and former Vice President Joe Biden, 77.

Abe, including through his "golf diplomacy," managed to build personal ties with Trump, a real estate mogul who was elected in 2016 with no experience in public office and who has proven to be unpredictable and unconventional in diplomacy.

The U.S. government, meanwhile, is also likely to pay attention to Japan's approach to China amid increasing U.S.-China confrontations over a raft of issues ranging from economic and technological matters to security and human rights.

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