Taiwan’s armed forces have carried out their first joint navy–coast guard anti-blockade drill, rehearsing how to protect commercial shipping if China attempts to cut the island off from vital supplies.

The exercise took place off Taiwan’s east coast as part of the 10-day Han Kuang war games. The navy and coast guard simulated escorting a merchant ship to safety while a minesweeper cleared a navigable channel and guided the vessel into port.

Taiwan’s defence ministry said the exercise was designed to test coordination between agencies and strengthen the island’s maritime resilience under combat conditions. The coast guard would play a supporting role alongside the navy during a conflict.

The drill reflects one of Taiwan’s most serious security concerns. Rather than immediately launching a full amphibious invasion, China could attempt a blockade or “quarantine” that restricts shipping, fuel, food and military supplies in an effort to force Taipei to accept Beijing’s terms.

China considers self-governed Taiwan part of its territory and has not ruled out the use of force to take control of the island. Taiwan’s democratically elected government rejects Beijing’s sovereignty claim and says only its people can decide their future.

Pressure has increased in recent months. China began what it calls law-enforcement patrols off Taiwan’s east coast in June, angering Taipei and raising concern in Washington and other Western capitals. The east coast has traditionally been viewed as less exposed than the Taiwan Strait, making the increased Chinese activity strategically significant.

Taiwan depends heavily on sea lanes for imported energy and raw materials. A blockade could create pressure without the enormous military risk of landing troops on defended beaches. It could also be presented by Beijing as a customs or law-enforcement action, complicating the international response and testing whether other countries are willing to escort commercial vessels.

The anti-blockade exercise was not the only defensive scenario rehearsed. Taiwanese troops also installed metal barricades, concrete obstacles and barbed wire on approaches to a major bridge in Taipei, preparing for the possibility of an assault on the capital.

Blockade planning has major global economic implications because Taiwan is central to the semiconductor supply chain. A prolonged disruption around the island could affect electronics, automobiles, telecommunications and advanced-computing industries worldwide.

It could also bring China and the United States into a dangerous confrontation. Washington does not maintain formal diplomatic relations with Taiwan but is required by US law to provide the island with the means to defend itself. The precise nature of any US military response remains deliberately unclear.

The latest drill does not mean a blockade is imminent. Annual war games are intended to test readiness, and governments routinely rehearse worst-case scenarios. The significance lies in the scenario chosen and the agencies involved: Taiwan is preparing not only to fight military forces but also to keep trade and civilian supply lines operating under pressure.

The use of a simulated merchant ship was therefore central to the exercise. It tested how military protection, coast-guard authority, mine clearance and port access would work together. In a real crisis, keeping even a limited corridor open could determine how long the island’s economy and essential services continue functioning.

As China expands patrols and Taiwan strengthens its response, the waters around the island are becoming increasingly crowded with military, coast-guard and commercial vessels. That raises the risk that a miscalculation or disputed inspection could escalate more quickly than either side intends.