What if the first wave of a Chinese attack on Taiwan were led by not warships and landing barges, but small civilian vessels with troops on board?
Last year, a former Chinese naval officer drove a speedboat from China’s Fujian province to one of the ports in Taiwan’s Tamsui River, claiming to want to escape from China for democracy.
In May, a Chinese man – who claimed to have crossed from China in a dinghy – posted videos of a flag he had planted on a beach in northern Taiwan.
And a month before that flag-planting (videos since removed; a report is here), a Chinese-crewed cruise ship registered in Bermuda sailed within 4 kilometres of Taiwan’s coastline.
These three cases are illustrative of a growing problem. Suspected Chinese incursions have managed not just to enter Taiwan’s waters, but to get extremely close to the coastline – sometimes near enough to land. Interrelated challenges explain how such vessels get close to Taiwan: the difficulty in detecting small boats, bureaucratic fragmentation, and how to justify denying access to non-military vessels under international law.
‘Testing the vulnerability’
Yes, a full-scale invasion of Taiwan would be extremely challenging, especially given the limited number of possible landing beaches, which are well-defended.
Yet such vulnerabilities could be exploited by China in various ways.
One possibility floated by analysts is an attempted decapitation of the Taiwanese government. A key vulnerability in this case is the Tamsui River, which runs into the heart of Taipei. A possible scenario, says Dr Siong-Ui Tsiam, an Assistant Research Fellow at Taiwan’s Institute for National Defence and Security Research (INDSR), is that Chinese special forces sail up the river in small boats and attempt to take out the government.
Military planners in Taipei are well aware of the risks. Satellite data suggests that China has built a mock-up of government buildings in Taipei – including the Presidential Office Building – at an army training base in Inner Mongolia. Taiwanese drills in July included practising blocking and defending the Tamsui River against Chinese hovercraft and other vessels. A decapitation attempt “would still be difficult” says Tsiam, noting the large military and police presence in the city centre.
It still may be one Beijing is considering. Referring to the Tamsui River case, Tsiam said “it’s highly likely he’s testing the vulnerability of our river and coastal defence.”
The first challenge Taiwan faces is in detection of such small boats. “The technology – radar, monitoring etc – is all designed for big ships,” said Tsiam.
Typically, ships are tracked using a combination of radar and Automatic Identification Systems (AIS), which broadcast positioning and navigation systems via radio and satellites. But small boats often can’t be picked up on radar. Meanwhile, under international law, small boats are not required to have AIS installed. The result is that the Coast Guard struggles to detect small boats, and even if they are sighted, the authorities often do not know the vessel’s identity.
AIS is the wild card
Bureaucratic fragmentation exacerbates the problem.
With more advanced systems, it is possible to detect small boats. In all likelihood, the Taiwanese navy is probably aware of at least some of them. But the division of authority between different government institutions presupposes a clear distinction between military and non-military activity, with the navy tasked with the former and the coastguard the latter.
As a result, the navy is focused on detection of military devices, said Dr Yun-hu Yeh, an Associate Professor at Central Police University in Taiwan, who emphasised that all views he expresses are his own. If the navy spots a small boat, “high-ranking officers always ignore this information,” he says, so it is not passed on to the coastguard, which is supposed to deal with it.
One possible response currently being discussed in government is new legislation requiring vessels to have AIS systems installed and turned on within Taiwan’s waters.
New regulations would require even small ships – of less than 20 tonnes – to purchase and install AIS systems. If Taiwan could easily identify its own fishing vessels, anything else could be easily flagged as suspicious, in theory making Chinese incursions easier to spot. That would help to combat smuggling from China, Vietnam, the Philippines and elsewhere, which includes drugs, small arms and human trafficking.
Fishermen who install AIS systems will be able to claim a subsidy of up to 20,000 Taiwan dollars ($6,500 USD) – which is the estimated cost of purchasing a system, according to government estimates. But it must meet certain requirements. Crucially, the subsidy excludes systems manufactured in China, which are often the cheapest, but may have a backdoor installed into the hardware or software.
“If there’s a conflict, China could switch all the AIS to fake systems,” noted Tsiam. If Taiwanese vessels started broadcasting false location or identification information, it would sow chaos, making it difficult for Taiwanese authorities to identify which ships are friendly.
AIS systems are also not perfect. For one, they can send out fake identification or location information. A recent paper by CSIS analysed AIS anomalies among purported fishing vessels to try to identify ostensibly civilian maritime assets being used by China, estimating that there were “serious flags around identity manipulation” for 209 vessels in 2024.
Tsiam believes that requiring non-Chinese-made AIS on small boats is a “necessary move.” But it’s not enough.
“Even with the law, we will still have a big problem,” he said. “This kind of regulation helps the government to monitor and regulate the situation, but the problem is still if we have enough budget and personnel for law enforcement.” Taiwan is moving, but slowly: the Coast Guard launched two new patrol vessels in October.
Bureaucratic fragmentation is rife
Yeh argues that bureaucratic fragmentation is the central problem here.
“We do not have a holistic system to control maritime transportation,” he said. Indeed, he adds, currently data is fragmented between the navy, Department of Transport and Coast Guard Authority. The latter has the vessels to respond to any issues, but it is the Department of Transport, which is a separate body, with the authority to deal with them. The Coast Guard does not have the authority to deal with behaviours such as AIS spoofing or turning off AIS.
Experts are often sceptical when small boats claim to have crossed the Taiwan Strait, which is extremely dangerous. In the case of the man planting a flag, the Coast Guard Authority Deputy DIrector-General noted that he did not appear dehydrated or sunburnt as you would expect after a long, arduous journey.
“We think there’s another boat that drops them off,” said Yeh. Detecting small boats is challenging, but it should be feasible to detect any larger vessels that are potentially suspicious. But here too Taiwan remains vulnerable.
Under Taiwanese law, Chinese-flag vessels are prohibited from passing through certain zones, such as Taiwan’s territorial seas and EEZ. But some of this area is international waters, so other vessels have a right to “innocent passage” through it. In the case of ships crewed by Chinese nationals but flying under a “Flag of Convenience,” Taiwan would have to have a justification to prevent them travelling through.
Still, if there is evidence of suspicious activity, the Coast Guard could respond – if it had the mandate to use discretion.
“You could just assign a sea lane to certain vessels for ‘innocent passage’ and you respond if any vessel fails to comply,” said Yeh.
A new system is under construction, but at present the Coast Guard is not authorised to use discretion for potentially suspicious activity. Such confusion helps explain how the cruise ship got so close to Taiwan.
“The Chinese government understands our loopholes clearly,” said Yeh, adding: “imagine a cruise ship that has People’s Liberation Army troops on it.”
