Executive Summary
Since 2017, China’s maritime activity in the waters between the South and East China Seas, notably around Taiwan and the Senkaku Islands, suggests that the People’s Liberation Army’s (PLA) strategic objective is to shift regional power dynamics in its favour. To deter China’s maritime assertiveness in the Pacific Ocean, the US approved an order for Japan to receive 400 Tomahawk cruise missiles, strengthening the US’ strategic objective of deterring Chinese aggression in the Pacific region. For the US to continue deterring Chinese maritime aggression, further strengthening Japan’s naval counter-strike capabilities is a strategy that US Pacific Command (USPACOM) must adopt.
Key Points
- On July 29, the Japanese Maritime Self-Defense Force (JMSDF) confirmed that the Japanese destroyer JS Chokai launched a Tomahawk cruise missile in the Pacific Ocean.
- The JMSDF’s live-fire test of a Tomahawk cruise missile demonstrates Japan’s strategic objective of expanding its long-range strike capability and strengthening its stand-off defence and counter-strike capabilities to deter aggression from China and North Korea in the Pacific security environment.
- The live-fire test follows the JS Chokai’s loading drills with US Navy personnel in San Diego, US, demonstrating the US’ role in supporting and expanding Japan’s defensive capabilities.
- Tomahawk cruise missiles are produced by US company RTX Corporation, strengthening the US–Japan security relationship through shared defence procurement.
Analysis
The current US security strategy for deterring a PLA invasion of Taiwan consists of maintaining US military superiority in the South China Sea while encouraging key allies to invest in their own deterrence capabilities to create a collective allied balance of power in East Asia that is superior to China’s military capabilities. The JMSDF’s live-fire test of a Tomahawk cruise missile suggests that Japan is strategically shifting toward a defensive maritime doctrine in the Pacific Ocean to counter-strike China’s maritime assertiveness. This is evident as China has been actively expanding its territorial claims in the East China Sea, particularly around the Senkaku Islands, further increasing its maritime presence in Japanese waters.
Correspondingly, the JMSDF’s live-fire test follows China’s recent maritime drills around the Taiwan Strait, signalling that although Taiwan and the Senkaku Islands are often framed as distinct Chinese strategic objectives, the PLA’s recent naval activity indicates that their proximity functions as a mutual tool for shifting regional power dynamics in the Pacific Ocean in China’s favour.
Taken together, the JMSDF’s introduction of the Tomahawk cruise missile into its naval capabilities suggests that expanding Japan’s stand-off defence and counter-strike capabilities can strengthen deterrence against Chinese mobilisation toward both Taiwan and the Senkaku Islands, further supporting the US strategic objective of defending Taiwan against a PLA amphibious invasion.
Furthermore, a spokesperson for China’s Ministry of National Defense characterised the JMSDF’s live-fire test as a security threat, suggesting that the PLA views Japan’s missile tests as an indicator of broader regional escalation. The JMSDF’s use of Tomahawk missiles reveals Japan’s strategic pivot toward a stronger military posture, transitioning from a reactive post-World War II national security strategy to an increasingly central role in the defence of Taiwan.
Policy Implications
- Expand Japan’s Stand-Off Weapons Arsenal: The US should provide Japan with additional US-produced stand-off weapons, such as the Tomahawk missile, to expand the JMSDF’s naval arsenal and enable Japan to conduct counter-strikes against mainland China from a safe maritime distance.
- Expand US–Japan Naval Exercises: The US should expand bilateral naval exercises focused on stand-off strike capabilities and conduct exercises in response to prospective Chinese maritime exercises in the South China Sea to deter a PLA amphibious assault on Taiwan.
- Strategic Monitoring Risks: Potential US–Japan missile exercises could be perceived by China as escalatory, creating a strategic concern for Japan over the possibility of a Chinese response. In turn, this suggests that US–Japan cooperation should balance strengthening deterrence against Taiwan while concurrently mitigating the risk of regional escalation.
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