A Japanese Maritime Self-Defense Force (JMSDF) destroyer transited the Taiwan Strait on April 17 for the first time in roughly ten months, prompting an immediate diplomatic protest from Beijing and a retaliatory naval demonstration near Japan's southwestern islands within days.
The sequence of events — a strait passage, a formal protest, and a close-range encounter between advanced warships — illustrates the escalating military signaling dynamic between Japan and China in the waters surrounding Taiwan and the Ryukyu island chain.
Multiple Japanese government officials and sources familiar with Japan-China relations confirmed to Kyodo News and other Japanese outlets that the destroyer JS Ikazuchi（いかづち）passed through the Taiwan Strait on April 17. This marked the fourth cumulative JMSDF strait transit, following previous passages in September 2024, February 2025, and June 2025.
This also marked the first JMSDF strait transit since Prime Minister Takaichi formed her cabinet in October 2024 and since her November 2024 parliamentary remarks linking a Taiwan contingency to Japan's "existential crisis situation" — making it the first such passage through this sensitive waterway under the current administration.
The Ikazuchi was not making a symbolic crossing. According to Japan's Joint Staff, the vessel was en route to the Philippines to participate in the multilateral Balikatan exercises, scheduled from April 20 to May 8, incorporating the Taiwan Strait passage as part of a broader Indo-Pacific deployment.
Japan's government did not proactively disclose the transit. The passage was instead revealed through Japanese media reports citing multiple government-affiliated sources.
Why the Gap: Managing Beijing's Narrative War
The approximately ten-month interval since the previous transit was not accidental, multiple officials and sources familiar with Japan-China relations indicated to Japanese media.
The gap followed Prime Minister Sanae Takaichi's (高市早苗) parliamentary remarks in November 2024, in which she explicitly linked a Taiwan contingency to Japan's "existential crisis situation" (存立危機事態) — a legal threshold under Japan's security legislation that could justify collective self-defense. Beijing reacted sharply, and Tokyo reportedly calculated that continuing strait transits at a similar tempo risked handing China a propaganda tool to frame Japan as signaling armed intervention in Taiwan.
Policy sources indicated that after Takaichi briefed major foreign leaders on the current state of Japan-China relations and Japan's own position, Tokyo assessed that the timing for resuming transits had become tenable. Japan has consistently maintained that JMSDF vessels retain the right to transit the strait under international law — a position aligned with that of the United States, which continues its own regular passages.
Beijing's Response: Sovereignty Claims and Diplomatic Pressure
China's Ministry of Foreign Affairs responded the same day. Deputy Spokesperson Guo Jiakun (郭嘉昆) stated at the April 17 regular press briefing that Beijing "firmly opposes" the transit, characterizing it as a "deliberate provocation," and said China had lodged a formal protest with Japan.
Guo reiterated Beijing's standard position — that Taiwan is Chinese territory and that China holds sovereignty and jurisdiction over the Taiwan Strait — and stated that the People's Liberation Army (PLA) had taken "necessary measures in accordance with law." He also directly criticized Takaichi's parliamentary statements on Taiwan, calling Japan's actions "mistake upon mistake" that damage the political foundation of Japan-China relations and threaten Chinese sovereignty and security.
Japan-China relations had already deteriorated notably since Takaichi took office, primarily over the "Taiwan contingency equals existential crisis" framing. Legal scholars note that Japan's invocation of this threshold carries significant operational implications under its 2015 security legislation, helping explain the sensitivity of Beijing's reaction.
The Stealth Ship Encounter: Military Signaling Near Japan's Southwest Islands
Within roughly 48 hours of the strait transit, two PLA Navy vessels were identified operating near Japan's southwestern islands. Japan's Joint Staff publicly released footage and details on April 20.
According to the Joint Staff announcement, JMSDF forces confirmed two eastward-bound Chinese naval vessels at approximately 11:00 a.m. on April 19, around 60 kilometers southwest of Yokoate Island (横当島) in Kagoshima Prefecture. The vessels were identified as a Luyang III-class (Type 052D) guided-missile destroyer (hull number 133) and a Jiangkai II-class (Type 054A) frigate (hull number 577) — both featuring hull designs that incorporate stealth considerations.
The two vessels proceeded northeast through the channel between Amami Oshima and Yokoate Island toward the Pacific. The JMSDF dispatched JS Yahagi (やはぎ) — the fifth vessel of the Mogami-class, Japan's newest generation of stealth-configured frigates, homeported at Maizuru and assigned to the newly reorganized Patrol and Guard Group established in March 2025 — to conduct surveillance and intelligence collection.
Japan's Defense Ministry used neutral language in its official release, referring to "confirmation of vessel movements" and "surveillance and intelligence-gathering operations." Multiple Japanese media outlets, however, described the encounter as PLA frontline warships operating in close proximity to Japanese territory, with a stealth-versus-stealth dynamic between the Mogami-class frigate and the PLA's Type 052D and 054A vessels — highlighting the intensifying military interactions around Japan's southwestern island chain.
