Japan this week restated its aim to rid the world of atomic weapons as it marks the 79th anniversary of the nuclear bombings of Hiroshima and Nagasaki — even as the Japanese government seeks assurances the United States would be willing to use its own nuclear arsenal to protect Japan.

At 8:15 a.m. Tuesday — the time that the atomic bomb exploded 600 meters (1,969 feet) above Hiroshima on August 6, 1945 — people across Japan marked a minute’s silence to remember the horrors visited on the city.

“It is the mission of Japan, the only country to have suffered nuclear war, to pass on the reality of the atomic bombings to future generations,” Japanese Prime Minister Fumio Kishida told delegates gathered in Hiroshima.

The manner of Japan’s defeat in World War II changed the country, driving an aversion to war and military power that lasted for generations. However, after decades of pacifism, the country is undergoing profound changes in its attitude to military power amid multiple regional threats, said Yee Kuang Heng, a professor of international relations at the University of Tokyo.

“The DPRK’s [North Korea’s] nuclear missile programs; Chinese military assertiveness and territorial claims in the East China Sea; Russia’s closer military cooperation with China in the past couple of years. These are underlying drivers that have been around for the past couple of years,” Heng told VOA.

“There is Prime Minister Kishida’s oft-quoted fear that Ukraine today could be East Asia tomorrow, especially with potential flashpoints close to Japan, such as Taiwan.”

Those threats prompted Japan to last year announce a doubling of defense spending, to 2% of gross domestic product by 2027.

Last week, the United States, Japan’s closest ally, announced a major upgrade of its military command in the country. During the visit by U.S. Secretary of State Antony Blinken and Secretary of Defense Lloyd Austin, Tokyo again sought assurances from the U.S. that it would be prepared to use “extended deterrence” — that is, nuclear weapons — to defend Japan.

“They have always had doubts about the American commitment to use all their might to defend them. And that includes nuclear weapons, which gives you some idea of just how somewhat paradoxical Japan’s supposed nuclear allergy is,” said Grant Newsham, a senior fellow at the Washington-based Center for Security Policy and a former U.S. Marines colonel who served in Japan.

For decades, anger among Asian neighbors over Japan’s actions in World War II prevented closer regional cooperation. That’s also changing, said analyst Heng.

“Countries like the Philippines, they’ve recently signed very important defense agreements with Japan, such as the Reciprocal Access Agreement, actually the first Asian country to do so with Japan,” he said. “South Korea, notably under President Yoon [Suk Yeol], has talked up a more forward-looking relationship with Japan.”

But 79 years after the trauma of defeat — the destruction of Hiroshima and Nagasaki — are the Japanese people ready to become a military power once more?

“There’s a sea change also in the public opinion in my country as well,” said Kunihiko Miyake of Japan’s Canon Institute for Global Studies.

“We are not rabbits. We are tortoises. We are probably slow, but we always go ahead, and one step forward at a time,” Miyake added. “Maybe this time, two or three steps forward.”

China has reacted with anger to the rapid changes in Japan’s military posture.

“During World War II, Japan invaded and colonized some Southeast Asian countries, including the Philippines, and committed serious historical crimes. Japan needs to seriously reflect on its history of aggression and act prudently in the field of military security,” said Lin Jian, a spokesperson for China’s Ministry of Foreign Affairs, during a press conference last month.

At the same time, say analysts, Japan must secure itself against multiple threats — not least from China itself.