TAIPEI (Taiwan News) — A paper by Washington, D.C.-based think showed two scenarios in which China imposed a quarantine over Taiwan to pressure Taipei and demonstrate Beijing's alleged sovereignty.
On June 5, the Center for Strategic and International Studies (CSIS) released a paper asserting that China is more likely to impose a quarantine on Taiwan in the short term rather than a full blockade. Under this scheme, Beijing would publicly announce stricter customs regulations and deploy coast guard ships to target ports like Kaohsiung, boarding "non-compliant" ships, thus establishing a “new normal” in the Taiwan Strait.
The report said the terms quarantine and blockade have been used interchangeably in the media to describe potential actions by China to isolate Taiwan. However, the authors defined quarantine as a “law enforcement–led operation to control maritime or air traffic within a specific area,” while a blockade is “foremost military in nature.”
The paper presented two scenarios of quarantines, with one limited in scope and the other comprehensive. In a limited quarantine, the goal is not to cut off Taiwan's trade routes but to engage in gray zone operations.
Days or weeks before the quarantine begins, Beijing would mobilize its coast guard's maritime law enforcement units, some military forces, and nearby maritime militia fishing vessels.
China would publicly announce “enhanced customs inspection rules,” avoiding terms like "quarantine" or "blockade." All cargo ships and oil tankers entering Taiwan would need to submit customs declarations to Chinese authorities in advance. Chinese maritime law enforcement personnel would be authorized to board and inspect ships, question crews, and take punitive steps against non-compliant vessels.
The quarantine measures would commence within 48 hours of the announcement. Chinese authorities would not disclose specific inspection locations, but the plan would be to target Taiwan's busiest port, Kaohsiung.
Chinese vessels would then infringe upon Taiwan’s 44-kilometer (24-nautical-mile) contiguous zone, occasionally approaching the 22-kilometer (12-nautical-mile) territorial sea boundary. These actions carry significant symbolic weight, as China does not recognize Taiwan's claims to these boundaries.
Approximately 20 maritime militia fishing vessels would support these maritime law enforcement ships. Although militia vessels lack the authority to board or search merchant ships, they could operate densely in specific areas to fill gaps in China's intelligence, surveillance, and reconnaissance (ISR).
The Chinese navy would deploy nearly 30 warships distributed into five surface action groups (SAGs) that would patrol around Taiwan to prevent intervention by foreign coast guards or militaries.
If China encounters minimal resistance and most companies comply with the new customs regulations, Beijing could begin scaling back operations after about a week.
However, a significant Chinese law enforcement and military presence around Taiwan would persist for the next few weeks, indicating a new normal.
The second scenario represents a significant escalation, where China announces new, “enhanced customs inspection rules” requiring cargo bound for Taiwan to report to Chinese authorities in advance. This time, China would publicly declare that the quarantine zone encompasses the entire island of Taiwan.
Beijing would deploy more coast guard and maritime law enforcement ships in an unprecedented large-scale operation, with more than 10 vessels around Kaohsiung alone. Additionally, over a dozen ships would be stationed at ports along the western coast, including Taipei and Taichung, with nine ships near Keelung, Taiwan's second-largest import hub.
Six ships would be dispatched to smaller eastern ports like Hualien and Su'ao. China would also deploy the Shandong aircraft carrier group southeast of Taiwan, with frequent J-15 sorties to the east of Taiwan.
In this second scenario, China would be more proactive in boarding and inspecting ships, intercepting at least one to two vessels daily, primarily targeting Taiwanese-flagged ships and ships from countries maintaining formal diplomatic relations with Taiwan. The uncertainty of Chinese enforcement would lead many shipping companies to delay shipments, significantly reducing cargo volumes to Taiwan.
These actions would continue for over two weeks before the intensity and frequency began to decrease. However, a substantial presence of Chinese coast guard and military forces would remain operational around Taiwan “indefinitely.”
The report notes that while China can successfully execute these quarantine operations, such actions are more complex than any measures Beijing has taken to date. Moreover, this approach carries significant risks for China, with its success largely dependent on the reactions of Taiwan, the U.S., and other countries.