How you would squeeze an island
Published 8 October 2026
Not every scenario involves landing craft. The Lowy Institute's Christopher Eylward published an argument on October 2 that Beijing could throttle Taiwan "without firing a shot". An armed naval blockade, he notes, counts as an act of war under the UN Charter and would give Taiwan's partners a clear basis to invoke collective self-defense. So Beijing is building the legal tools for something else. The Coast Guard Law, the revised Maritime Traffic Safety Law and a 2024 Coast Guard order give Chinese maritime enforcement agencies domestic authority, as Beijing sees it, "to board, inspect, and detain foreign vessels in claimed jurisdictional waters". The result is what he calls "a civilian-led administrative quarantine".
The mechanics are bureaucratic. Beijing could demand advance customs manifests from ships bound for Kaohsiung, which handles about 57% of Taiwan's maritime trade by value. Ships that did not comply would face inspection under the pretext of anti-smuggling, biosecurity or maritime safety checks. The effect on shipping would come from insurers, not warships. Once boarding begins, Eylward argues, insurers could demand prohibitive war-risk premiums, and shipmasters would divert their cargo. "The operational effectiveness of a quarantine does not rely on sinking merchant vessels," he writes; "it exploits the mechanics of global maritime finance". He cites CSIS and Naval War College work on a "Kinmen model," in which Coast Guard patrols inside contiguous waters become routine and then become a template.
Then the energy numbers decide it. The Lowy piece says Taiwan keeps operational LNG storage of only 14 days, and that diverting a handful of tankers could force rationing across households and chip plants. The Atlantic Council's Kevin Li, writing in March at the start of the Iran war, gave a different figure: "Taiwan only has 11 days of natural gas inventories in reserve," well below South Korea and Japan. The primary figure comes from the US Energy Information Administration's Taiwan Analysis Brief, last updated April 2026, which cites the Ministry of Economic Affairs: "In 2026, the Ministry of Economic Affairs estimated that Taiwan's stock of natural gas was enough to cover 10 to 11 days of use." That matches Li and makes Lowy's 14 days the outlier, so the range is printed with its year and its origin. Either way, it is under a fortnight. Li also reported that Taiwan imported 95 percent of its energy in 2025, over 99 percent of its oil and gas, and that gas share in power generation had risen from around 17 percent in 2006 to nearly 48 percent in 2025. The EIA says the island imported over 94% of its energy demand in 2024, and that primary energy production has fallen each year since 2020, from 0.41 quads in 2019 to 0.26 in 2024, as Taiwan closed its last operating nuclear plant in 2025. In 2024 nearly all domestic production was nuclear (47%) and non-hydro renewables (47%). The Iran war showed the island what a gas shock looks like without any Chinese ship being involved. A shock in another strait can squeeze the island before an operation in its own strait begins.
The EIA adds the structure of the problem. Taiwan produced 2.1 Bcf of natural gas in 2024 against consumption of 1,021 Bcf, almost entirely imported as LNG through three regasification terminals with total capacity of 1,013 Bcf. Power generation used 78% of gas and industry 15%. For oil, the Ministry of Economic Affairs estimated stockpiles at 146 days in 2024. Taiwan imported 794,000 barrels per day of crude and condensate in 2025, up 4%, mainly from the Middle East and the United States, entering through three ports: Mai Liao (55%), Kaohsiung (30%) and Shalung (15%). Petroleum product imports were about 293,000 b/d in 2025, with Russia the largest source at 38%. Taiwan depends completely on imports to meet domestic coal demand. About 76% of coal use in 2024 went to power generation; coal supplied 40% of total electricity generation. Coal consumption was 63 million short tons, the third straight annual decline. The sourced numbers say a quarantine or blockade bites first on LNG at 10 to 11 days of stock and then on oil at 146 days, and the single "days until collapse" claim is deliberately avoided here. TSMC alone takes almost 10 percent of the island's electricity, and electronics and electrical equipment manufacturing nearly a quarter. Summer demand in July has been up to 40 percent above February.
Eylward also describes the dilemma a quarantine would pose Taipei. Sending civilian Coast Guard cutters to meet the boarding concedes Beijing's premise that this is an internal administrative matter. Sending navy escorts for tankers lets Beijing say Taiwan militarized a customs operation, and gives its navy a pretext to step in. His prescriptions are a multinational marine reinsurance backstop, allied Coast Guard presence in the strait and a challenge under World Trade Organization rules, since Taiwan is a separate customs territory. These are one analyst's proposals, not policy.
The southern edge of the problem is a channel. Reuters' October 31, 2025 report said that American troops and anti-ship missiles have been deployed to the northern Philippines in "almost continuous, joint war drills," with one goal "to block the Bashi Channel and deny Chinese warships access to the Pacific Ocean if Beijing launches an attack on Taiwan." Batanes province, with about 20,000 residents, lies less than 90 miles from Taiwan on the southern edge of the Bashi Channel. Retired Philippine Rear Admiral Rommel Ong says: "We should have the ability to deny the Chinese control of the Bashi Channel... that decisive point will determine who wins or who loses." US Marines of the 3d Marine Littoral Regiment deployed the Navy-Marine Expeditionary Ship Interdiction System to Batan Island for the first time during Balikatan 2025, on Saturday, April 26, 2025, according to a PACOM article of April 28. Reuters says American forces twice airlifted anti-ship missile launchers there in April to June 2025 exercises. Locals' view from Reuters: residents were "terrified" at the first helicopter drill in April 2023.
Taiwan's own defense planners describe the same picture. The Ministry of National Defense's 2025 Quadrennial Defense Review says the PLA "has built a large inventory of navy and coast guard vessels that can work in tandem to isolate or blockade key ports and shipping routes around the main island of Taiwan," and that forces positioned around the island "could rapidly execute a blockade or transition to a direct invasion." In an invasion, it says, the PLA would use "amphibious transports - including conscripted civilian roll-on/roll-off ferries - together with helicopters and transport aircraft" and its priority would be to "seize critical ports, beaches, and airfields to establish a lodgment". The review defines gray-zone operations as aimed to "test and wear down our combat readiness and training, while intensifying psychological intimidation". Its strategy is "Defensive Posture, Layered Deterrence," with "Multi-Domain Denial, Resilient Defense" as the operating approach, including more training for conscripts and reserves. Note that the review itself describes a ferry-borne landing, not a Normandy-style armada, and that matches the Reuters source's phrase about the difficulty of the operation.
Notice how this connects to the American statute. The Taiwan Relations Act names "boycotts or embargoes" among the non-peaceful means of grave concern. A customs quarantine is exactly the gray case that the 1979 drafters put on the list.