U.S. President Joe Biden will embark later in May on his first trip to Asia since taking office, a sign that Washington is not taking its eyes off China's assertiveness in the region even in the midst of Russia's war in Ukraine.

With the Ukraine crisis bringing renewed attention to Taiwan, another democracy living in the shadow of a powerful authoritarian neighbor, Biden, while in Japan, is expected to showcase the robustness of the bilateral alliance as it is a key part of efforts to deter Beijing's potential aggression over Taiwan and its vicinity.

US President Joe Biden speaks at the White House Correspondents' dinner in Washington on April 30, 2022. (UPI/Kyodo)

"The Biden administration, rightly so, has been spending lots of time on Ukraine and Europe. So I think the administration really wants to show Asian people...and of course indirectly to China...that Ukraine is important but at the same time Asia is important," said Satohiro Akimoto, an expert on Japan issues who leads the Sasakawa Peace Foundation USA.

During his five-day trip from May 20, which will also take him to South Korea, Biden will meet with the leaders of the two Asian allies and attend a summit of the "Quad" group of Indo-Pacific democracies -- the United States, Japan, Australia and India -- to push for a "free and open Indo-Pacific."

For Japanese Prime Minister Fumio Kishida, the scheduled meeting with Biden on May 23 will be their first in-person official bilateral talks in their respective capacities. Biden took office in January last year, and Kishida in October.

Prime Minister Fumio Kishida speaks at a government panel meeting on May 10, 2022, in Tokyo. (Kyodo)

The two are likely to agree to continue moving in lockstep in dealing with Russia's invasion of Ukraine, highlighting their resolve not to tolerate attempts to change the status quo by force in any part of the world, said Yuki Tatsumi, a senior fellow at the Stimson Center, a Washington-based think tank.

"And that would also send a message to China," the expert on East Asian issues added.

Japan has been hardening its stance toward China as Beijing has stepped up its territorial claims in neighboring waters and pressured Taiwan. China views the self-ruled democratic island as a renegade province to be reunified with the mainland, by force if necessary.

A Taiwan contingency is a particular concern for Japan as the country could quickly be drawn into a conflict, given the close proximity of its islands in the southwest -- including the Senkakus, a group of East China Sea islets controlled by Tokyo but claimed by Beijing.

Japan also hosts some 54,000 U.S. troops, many of them located in the southern prefecture of Okinawa, which would likely be involved should the United States decide to execute military operations for the defense of Taiwan.

The Ukraine crisis, coupled with China's accelerating nuclear buildup and North Korea's repeated missile tests, has generated a fresh drive in Tokyo toward strengthening the Japan-U.S. alliance, including by drastically reinforcing its own defense capabilities.

But moves to enhance deterrence through new capabilities or policies could still face hurdles in Japan, a country whose use of force is constrained by a war-renouncing Constitution.

Tatsumi expressed uneasiness over recent "sensational" ideas -- such as whether to acquire enemy base strike capability or seek a NATO-like nuclear-sharing arrangement with the United States -- becoming buzzwords in Japan without in-depth discussions over the armaments, costs or procedures to realize them.

Citing the nonnuclear principles Japan upholds as the only country in the world to have been attacked with atomic bombs, Kishida has already rejected the idea of hosting U.S. nuclear weapons on the country's soil, like some nonnuclear members of the North Atlantic Treaty Organization do, a move some experts say could increase the reliability of the U.S. nuclear umbrella.

Otherwise, the Japanese government has vowed to put all options on the table as it considers ways to strengthen its defense capabilities, including the ability to conduct missile strikes on enemy territory.

For decades, Japan has maintained that hitting foreign bases to counter an imminent attack by missiles or other threats would be permitted under the Constitution as long as it could be considered a self-defense measure. But so far, Japan has opted not to possess such a capability.

"I think the United States would be currently open-armed about the enemy base attack capability as part of the alliance's deterrence against China," Tatsumi said, but added that Japan should coordinate closely with the United States before making a decision on the issue, including over Tokyo's role in strike missions and whether they would be combined operations or conducted alone.

Former Japanese Prime Minister Shinzo Abe, who remains an influential politician, has been doubling down on his assertion that the United States should make clear it will defend Taiwan against any attempted Chinese invasion, calling for an end to Washington's longstanding "strategic ambiguity" policy.

The policy is intended not only to deter China from using force against Taiwan but also to dissuade Taiwan from seeking independence, as neither Beijing nor Taipei can feel certain about U.S. intervention to defend the island should a conflict arise, experts say.

Abe said in an opinion piece for the media organization Project Syndicate in April that the policy worked "extremely well as long as the United States was strong enough to maintain it, and as long as China was far inferior to the United States in military power."

But he said "those days are over" and such a U.S. policy on Taiwan is "now fostering instability in the Indo-Pacific region, by encouraging China to underestimate U.S. resolve, while making the government in Taipei unnecessarily anxious."

Tatsumi suggested that Japan may do well to address its own ambiguity regarding its level of involvement over a Taiwan attack if it wants to ask for a change in U.S. policy.

Various contingency scenarios can be explored, with experts pointing to the possibility of U.S. bases in Japan coming under preemptive attack by China to delay American military intervention to defend Taiwan, or a simultaneous invasion of the Senkaku Islands, which are just 170 kilometers away from Taiwan.

Akimoto said Japan and the United States should consider ways to deter China from taking assertive actions in a "holistic way" by looking into areas of military and economic security, such as supply chain resilience, cyber, technology and intelligence.

"The United States certainly doesn't want to drastically change the status quo in Asia," he said, calling it "very important" to move in gradual steps. But whether the two countries can come up with steps that are fast and effective enough to counter China will be "a challenge to both leaders," he added.

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