Japan's new prime minister, Shigeru Ishiba, who began his term this week, may advocate for forming a nuclear body with the United States that is similar to an arrangement between the U.S. and South Korea aimed at planning for nuclear warfare contingencies.
"The U.S.-ROK [Republic of Korea, or South Korea] approach is probably a good example of where the U.S. and Japan might go in the future if nuclear threats keep increasing," said James Schoff, a senior director of the U.S.-Japan NEXT Alliance Initiative at the Sasakawa Peace Foundation USA.
"It's not about nuclear sharing or Japan building its own nuclear forces — both politically impossible at the moment and not necessary — but [about] the alliance taking more practical steps to be prepared for U.S. nuclear retaliation, if it becomes necessary," Schoff said.
He said creating such a body would demonstrate resolve, credibility and readiness to any potential adversary and thus deter nuclear use in the first place.
Nuclear talk body
The new body would resemble the Nuclear Consultative Group (NCG) that South Korea and the United States established as part of the Washington Declaration in April 2023. The Washington-Seoul nuclear body is aimed at planning for potential nuclear contingencies caused by North Korea.
A U.S.-Japan nuclear consultative body would focus on nuclear threats from China and Russia in addition to North Korea, analysts say.
In a joint statement issued at their Security Consultative Committee meeting in July, Tokyo and Washington shared concerns over China's "rapid expansion of its nuclear weapons arsenal" and agreed to strengthen deterrence through their ongoing Extended Deterrence Dialogue.
"Ishiba is likely to continue the strategies of [his predecessor Fumio] Kishida against China, and may in fact try to be bolder," said Ryo Hinata-Yamaguchi, a nonresident senior fellow at the Atlantic Council's Indo-Pacific Security Initiative and an associate professor at Tokyo International University.
Countering China
Though he is not entirely anti-China, Ishiba, a former defense minister who analysts say tends to view foreign relations through a security framework, is expected to be tough on China's military assertions.
"Prime Minister Ishiba has spoken openly about the serious security challenges China poses to Japan," said Ken Weinstein, the Japan chair at Hudson Institute.
"These challenges lie behind his desire for an Asian NATO and nuclear sharing, neither of which is likely to be policy," Weinstein continued. "Instead, we are likely to see a change in tone towards the PRC with a tougher line from the Kantei on Chinese provocations than we saw from the more establishmentarian Kishida government."
The People's Republic of China (PRC) is the official name of China, and the Kantei refers to the Japanese prime minister's office.
Before Ishiba was elected, he wrote an article published in September by the Hudson Institute, an American conservative non-profit think tank based in Washington D.C., advocating for an Asian version of NATO that would consider sharing U.S. nuclear weapons or introducing nuclear weapons in the region.
He said if nuclear threats by China and North Korea escalate in the region, "the U.S. extended deterrence in the region will no longer function."
Extended deterrence involves a U.S. commitment to use all military assets, including nuclear weapons, to defend the region. Such a commitment would deter potential adversaries from causing any conflict.
But in recent years, there has been growing skepticism among U.S. allies over its extended deterrence commitment, leading South Korea to call for its own nuclear weapons.
In January 2023, South Korean President Yoon Suk Yeol said South Korea may have to consider developing its own nuclear weapons or ask the U.S. to redeploy nuclear weapons in South Korea.
Yoon later retracted his statement after the NCG was created in April 2023, saying that South Korea will instead focus on enhancing deterrence with the United States to deal with North Korea's nuclear threat.
Asian NATO
Ishiba's call for a collective security arrangement like an Asian NATO and nuclear deployment and sharing options stems from uncertainty in relying "solely on the security alliance with the U.S.," said Daniel Sneider, a lecturer in international policy focusing on Japanese foreign policy at Stanford University.
Ishiba sees "the need to protect Taiwan from Chinese attempts to forcefully reunify" the self-governed island that Beijing considers its own territory. He also wants Japan "to be prepared for any eventualities, including the retreat of the United States from global leadership," amid concerns over U.S. foreign policy after the presidential election in November, Sneider said.
Before Japan's own election this month, Ishiba, as a member of the Japanese Liberal Democratic Party, visited Taiwan in August and told Taiwan President Lai Ching-te that enhanced deterrence was necessary to resist China's aggression in the Taiwan Strait.
The Sasakawa Peace Foundation's Schoff said Ishiba probably knows that a true Asian NATO is not feasible, but "he is sending a signal to China and Russia that their aggressive use of military forces harassing other countries and penetrating their sovereign space is being noticed and will push Asian countries closer together in collective defense if they keep it up."
Japan accused a Chinese spy plane of violating its airspace for the first time in August.
Matthew Brummer, a professor at the National Graduate Institute for Policy Studies in Tokyo, said instead of calling for an Asian NATO, Japan will likely increase cooperation with NATO countries, deepening security agreements, especially regarding joint technology sharing and production.