Kyodo News / AP Japan's new warship "Izumo", which has a flight deck that is nearly 250 meters (820 feet) long, is unveiled in Yokohama, south of Tokyo, Tuesday, Aug. 6, 2013.

On Aug. 6, Japan launched its largest warship since World War II in a fresh demonstration of Tokyo’s steadily expanding naval capabilities. The unveiling of the destroyer — with a conspicuously large flight deck — has drawn attention from its neighbors, especially longstanding regional rival China, which in the past decade has embarked on a massive program of military modernization.

Japan’s pacifist constitution, which was largely drafted by the U.S. after the war, renounces the use of force for purposes other than self-defense. That means the country has no offensive arsenal of long-range missiles, aircraft carriers or similar weapons of aggression. The Izumo, which can be used to launch helicopters, still doesn’t cross the line, the Japanese government says. But the almost 20,000-ton vessel is capable of carrying up to fourteen helicopters, with a maximum of five taking off and landing at once according to Bloomberg. It’s set to be deployed by March of 2015. Tokyo says that the Izumo cannot carry planes, since it lacks the catapults necessary for seaborne take-off. Instead, officials maintain that the carrier will be used for disaster and rescue missions — in the aftermath of a tsunami, perhaps — as well as for responding to “various contingencies in waters near Japan,” reports broadcaster NHK.

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But Chinese officials, who remain cognizant of Japan’s savage invasion and occupation of China some seven decades ago, say they aren’t fooled. The helicopter carrier could be easily retrofitted for fighter jet capability, Zhang Junshe, a senior researcher at the People’s Liberation Army Naval Military Studies Research Institute, told the state-run China Daily. “It is an aircraft carrier, and Japan just called it a helicopter destroyer to downplay its aggressive nature,” he said. (China recently debuted its first aircraft carrier, the Liaoning,a refurbished Soviet-era vessel.)

In recent years, territorial disputes between Japan and China have flared over uninhabited islands that Tokyo administers but Beijing claims. The return to power of Japanese Prime Minister Shinzo Abe, who campaigned on a nationalist platform, and the rise of Xi Jinping, China’s new patriotically minded President, have further heightened distrust between the world’s second and third largest economies.

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The Chinese remain aggrieved that Tokyo has, to this day, only offered fumbling apologies for the savage bloodshed inflicted during World War II (apologies that are then undermined by the unrepentant utterances of Japanese right-wingers). Japan meanwhile frets over China’s increasing regional assertiveness as the budding global power flexes new muscles in the neighborhood. Tokyo’s response has been to place a new emphasis on its military capacity. In January, the country boosted its defense spending for the first time in a decade, albeit by 0.8%. Japan is also considering whether to ease restrictions on the use of its military, which is currently barred by the constitution from almost all activities but national defense. China’s 2013 military spending, revealed in March, increased by 10.7% over the last year, although foreign analysts believe the hike may be even higher.

The spats between the two countries have stoked public sentiment on either side. A survey published Aug. 5 by Genron NPO, a Japanese think tank, and China Daily found that more than 90% of Japanese and Chinese citizens had unfavorable views of the other country. Last year, 64.5% of Chinese citizens reported unfavorable feelings toward Japan, while 84.3% of Japanese felt the same way of their neighbors to the west.

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