The Japanese government called out China as posing "an unprecedented and the greatest strategic challenge" for Tokyo and its allies, using a notably sharper language than usual in its latest defense white paper.

The annual document focuses on the current threats Japan is facing and the country's defense efforts. According to the 2025 paper, Beijing is expanding the areas in which it operates and becoming increasingly assertive.

"International society is in a new crisis era and faces the biggest challenges since the end of World War II," Japanese officials said in the report issued this week, adding that China's "intensified military activities" are likely to continue and could "seriously impact Japan's security, which is a cause of grave concern."

Russia boosting its influence in Asia

The document also highlighted the growing offensive capabilities of North Korea and its deepening security and economic alliance with Russia.

"Russia has also been observed engaging in joint activities with China involving aircraft and vessels," according to Defense Minister Gen Nakatani.

Analysts say the wording of this year's white paper reflects a string of military incidents in the last 12 months.

"In the last year, there has been a lot more activity involving China, North Korea and Russia, so it is no surprise that Japan is expressing its concerns more explicitly," said Ryo Hinata-Yamaguchi, an associate professor at Tokyo International University's Institute for International Strategy.

He added that the security environment was "constantly changing."

More risky encounters between Chinese and Japanese forces

These changes are also illustrated by increasingly frequent confrontations between Chinese and Japanese troops.

On July 7, a Japanese YS-11EB electronic surveillance aircraft operating in international air space over the East China Sea was intercepted by a Chinese JH-7 fighter-bomber, with the Chinese aircraft closing to within 30 meters (100 feet), according to the Japanese Defense Ministry. Another Chinese aircraft performed a nearly identical maneuver the following day.

Through diplomatic and defense channels, Tokyo expressed "serious concerns" at the "abnormal approaches."

Beijing refused to accept the complaint and accused Japan of "coming close and spying on China's normal activities."

A similar incident took place in mid-June, when Chinese fighters operating from the aircraft carrier Shandong in the Pacific took up station around 45 meters from a Japanese P-3C reconnaissance aircraft for about 120 minutes.

Over the last year, Chinese coast guard vessels and aircraft have been seen on hundreds of occasions operating in waters around the uninhabited Senkaku Islands, also known as the Diaoyu Islands, which Tokyo controls but China claims. A large Chinese buoy was also found inside the waters around the East China Sea archipelago.

Japanese fighters scramble to intercept Chinese jet

In August 2024, a Chinese military reconnaissance plane intruded into Japanese airspace over the Danjo Islands, part of Nagasaki Prefecture in the far southwest, causing Japanese fighters to scramble to intercept the aircraft. Tokyo also responded to the incident by summoning the charge d'affaires at the Chinese embassy to the Japanese Foreign Ministry.

"As well as these acts, China is being even more assertive in the South China Sea and in the Taiwan Strait and that is a pattern that we have also seen increasing year-on-year," said Hinata-Yamaguchi.  

What did China say?

Beijing was quick to hit back against the white paper, with its Foreign Ministry saying the Japanese document "reflects a wrong perception of China, interferes in China's internal affairs and peddles the false 'China threat,'" according to Chinese Global Times paper.

Chinese Foreign Ministry spokesman Lin Jian also reminded reporters in Beijing that 2025 marks the 80th anniversary "of the victory of the Chinese People's War of Resistance Against Japanese Aggression."

"We urge Japan to deeply reflect on its historical crime, draw lessons from history and stop finding pretexts for its military buildup by talking up 'tensions' in the neighborhood," he was quoted as saying by the state-run daily.

Japan seeking to reassure Washington

The Japanese white paper did mention that Tokyo is on course to meet its goal of increasing defense spending to 2% of GDP by 2027, up from 1.8% at present.

And while that figure is still significantly below the 5% that the US is presently demanding that its allies spend on defense, Hinata-Yamaguchi said the white paper also contains a message for Washington.

"Reading through the document it is clear that there is new concern about the alliance," he said. "It is not stated overtly, but reading between the lines you can see that Tokyo is telling the US that it is doing everything that it can to take greater responsibility for its own defense and that it wants the US to have confidence in it as an ally and a partner."

Russia and China's joint show of force

Yakov Zinberg, a professor of international relations at Tokyo's Kokushikan University, said the latest white paper also hints at deepening concerns that China is building military alliances with North Korea and, more importantly, Russia in Northeast Asia.

"China and Russia have carried out a number of maritime and aerial military exercises in the last couple of years and I think it is very likely that there will be more such joint drills in the future," he said, suggesting that the intention is to demonstrate the nations' combined power and deter Japan from a more active resistance.

In one maritime drill last year, a joint fleet of Chinese and Russian warships circumnavigated the Japanese archipelago in what was widely interpreted as a show of force.

"Japan is extremely worried about this US administration and its commitment to the security alliance because President [Donald] Trump is simply so unpredictable," Zinberg said.

Edited by: Darko Janjevic