"An armed naval blockade is categorised as an act of war under the United Nations Charter, establishing a clear casus belli to activate collective self-defence commitments under Article 51.
To neutralise this trigger under international law in the case of Taiwan, China is operationalising legal warfare. Instruments including the Coast Guard Law, the revised Maritime Traffic Safety Law, and the 2024 Coast Guard Order No. 3 grant Chinese maritime enforcement agencies domestic authority to board, inspect, and detain foreign vessels in claimed jurisdictional waters.
Beijing is substituting the traditional concept of a sovereign naval blockade with a civilian-led administrative quarantine.
The China Coast Guard's routine incursions across Taiwan's restricted offshore waters represent the operational testing of an asymmetric siege mechanism, one designed to bypass Western defence doctrines entirely. Over the next 12 to 24 months, the People's Republic of China (PRC) may use domestic statutory mandates, customs safety declarations, and paramilitary assets to achieve the economic isolation of Taiwan without crossing the formal threshold of kinetic warfare…"
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Armand