Taiwan’s military on Monday commenced a five-day “Immediate Combat Readiness Exercise” designed to test its ability to shift rapidly from peacetime to full combat operations. The drill, which runs until 26 June, was announced hours after the defence ministry in Taipei said 21 Chinese military aircraft – including J-16 fighters, KJ-500 early-warning planes and a Y-20 tanker – had entered the island’s southwestern airspace, with 19 of them crossing into the Western Pacific for what Beijing described as “long-distance training over open seas”. According to Taiwan’s defence ministry, the exercise will involve “actual troops, on actual terrain, in real time, using actual equipment” and is built around a scenario in which China suddenly transforms one of its routine manoeuvres around the island into a real attack.

Taipei’s security planners view the drill as a direct response to an evolving form of coercion that falls below the threshold of war. A senior official at Taiwan’s National Security Institute told local media that Beijing is increasingly employing “grey-zone” tactics, including coast guard patrols, research vessels and legal claims, to erode the island’s control of its exclusive economic zones and the median line in the Taiwan Strait. The same assessment argued that Taiwan should emulate the Philippines’ policy of “absolute transparency” – publicly documenting every Chinese maritime intrusion – to counter disinformation and rally international support.

Beijing’s state media projected a different logic, reporting that recent scientific survey missions east of Taiwan were part of “territorial spatial planning” and accusing Japan and the Philippines of trying to present a fait accompli through bilateral negotiations on maritime boundaries. Chinese outlets said the talks, which cover waters Beijing claims as sovereign, are an attempt to “violate China’s legitimate maritime rights and interests”. That triangular dynamic – with Taiwan, Japan and the Philippines all facing overlapping Chinese assertions – reinforces the island’s security dilemma: the immediate trigger for the drill is aerial activity, but the broader operational environment increasingly includes contested waters where non-military vessels are used to press claims.

Coinciding with the drill, the first batch of US-made MQ-9B SkyGuardian drones has arrived in Taiwan, with assembly and flight testing underway. Analysts cited by the Liberty Times stressed that the drones’ main value lies in interoperability with US and allied forces, enabling real-time intelligence-sharing and filling gaps in round-the-clock maritime surveillance. The combat readiness exercise is a precursor to Taiwan’s main annual Han Kuang wargames, expected in August. With China’s Ministry of National Defence not responding to requests for comment over the weekend, regional observers note that the crowding of live-fire exercises, drone deliveries and legal brinkmanship heightens the risk of miscalculation.