Japan's Military Expansion Rattles China

China has sharply escalated its criticism of Japan's defense buildup, warning that Tokyo's expanding military capabilities could undermine regional stability and revive dangerous historical tensions in East Asia. China's Ministry of National Defense voiced this criticism on August 27th, interpreting Japan's military investments as a potential re-emergence of past conflicts.

Jang Shaolong stated that if Japan were allowed to rearm and become a war-capable state, the tragic history may well repeat itself. Beijing interprets Japan's procurement efforts as a shift toward long-range offensive power, accusing Tokyo of pursuing a war-capable state status that goes beyond post-war defense limitations.

Japan plans to establish three new departments within its defense ministry by 2027, a move that Beijing views as building institutional machinery for an ambitious military strategy. This restructuring suggests Japan is preparing for more complex and technologically advanced defense operations.

Japan's latest defense planning describes unmanned assets as an important part of future warfare, as they can reduce risks to military personnel, remain deployed for longer periods, and perform missions traditionally requiring crewed aircraft, ships, or ground vehicles. Japan is actively developing unmanned underwater vehicles (UUVs) to enhance its capabilities in underwater surveillance and operations.

The Chinese Defense Ministry has highlighted reports indicating Japan's intent to equip unmanned underwater vehicles with long-range missiles. This potential development is seen as politically and militarily significant, as it would combine two major elements of Japan's modernization: unmanned platforms and standoff weapons, marking a significant friction point. Currently, this remains a reported plan rather than a confirmed operational capability.

Japanese officials strongly reject China's interpretation, maintaining that its standoff missiles remain part of the minimum capabilities required for national self-defense and would operate within Japan's legal and constitutional framework. Japan is actively developing Type 12 surface-to-ship missiles and hypersonic weapons, alongside integrating Tomahawk cruise missiles into its arsenal. Tokyo consistently asserts that these systems are strictly for self-defense and adhere to its legal and constitutional boundaries, aiming to strengthen deterrence.

Japanese officials instead point to what they describe as an increasingly severe security environment, highlighting China's naval growth and North Korea's nuclear program as key concerns. Russia's escalating military activity near Japan is also cited as a growing security pressure, making stronger defense capabilities increasingly unavoidable.

On August 18th, Japanese Defense Minister Shinjiro Cooisumi and Australian Deputy Prime Minister and Defense Minister Richard Morals agreed to deepen cooperation involving Australian military testing ranges. The two governments committed to developing arrangements that could support testing of new military equipment, advanced weapons, autonomous capabilities, and next-generation long-range precision strike systems.

Crucially, that cooperation includes support for Japan's hypersonic missile program, with Australia offering its testing grounds. Testing long-range missiles in Australia marks a major step in cooperation, demonstrating how partnerships now drive Japan's defense evolution more than solo efforts.

Beijing is watching Japan build those capabilities while simultaneously creating a denser network of defense relationships across the Indo-Pacific. China is particularly wary of Japan establishing an integrated network of security partnerships, viewing the Indo-Pacific region as seeing increased integration beyond traditional diplomatic ties.

Both governments state that these steps are intended to strengthen deterrence and contribute to a free, open, and stable Indo-Pacific. Cooperation between Japan and Australia covers technology, training, and defense production, with shared goals of regional stability and deterrence against threats.

Japan's 2026 defense policy is placing increasing emphasis on artificial intelligence, unmanned platforms, defense production, and emerging forms of warfare. The nation is aiming for forces that are more survivable and technologically advanced, focusing on AI, unmanned platforms, and long-range capabilities as core elements of its modernized defense.

Tokyo says those pressures make stronger defense capabilities increasingly unavoidable, citing intense Chinese naval and air activity near Japan. Ongoing concerns over the Senkaku Islands (Diaoyu Islands), North Korean missile developments, and Russian military activity all contribute to an increasingly severe security environment that drives Japan's military buildup.

By warning about Japan becoming a war-capable state, China is attempting to frame the debate not as an ordinary military modernization program, but as a fundamental question about whether East Asia's post-war security order is beginning to change. This dispute merges modern security concerns with unresolved historical tensions, as China labels Japan as becoming a 'war-capable state'.

That is why the argument surrounding unmanned underwater vehicles and hypersonic missile testing carries much greater significance than the individual weapons themselves. Combining underwater stealth with long-range weapons significantly affects naval planning, while hypersonic weapons shorten reaction times for interception, altering the dynamics of strike capabilities.

For now, China's latest warning is another clear sign that Japan's military transformation has become one of the most sensitive strategic issues in East Asia. The debate now concerns the future balance of power in the Indo-Pacific, underscoring the strategic rivalry that will shape regional stability.