Taiwan is scrambling to secure its communications with the outside world against an attack by China, but even in peacetime cannot quickly repair critical undersea internet cables and lacks suitable satellite backups, experts and officials say.
China, which has never renounced the use of force to bring Taiwan under its control, has ramped up military and political efforts to force the democratically governed island to accept its sovereignty.
The Ukraine war has lent new urgency to Taiwan's efforts to bolster its security, especially against Chinese cyber attacks or attempts to sever any of 14 cables that connect it to the global internet.
"Strategic communications, internally and externally, is what keeps us up at night, particularly in the aftermath of Ukraine," said Tzeng Yisuo, an analyst at Taiwan's top military think tank, the Institute for National Defence and Security Research.
Taiwan has zeroed in on low-Earth orbit satellites as a solution, and has launched a two-year trial programme to boost internet services by leaning on international satellite providers.
Taiwan's total satellite bandwidth is about 0.02 per cent of what its undersea cables provide, according to Kenny Huang, chief executive at Taiwan Network Information Center, the island's internet domain manager.
Huang said Taiwan has struggled to attract interest from international satellite companies because of strict regulations on ownership, which limit foreign shares to a maximum of 49 per cent, and a lack of financial sweeteners.
"There's little incentive for them (foreign companies)," he said. "Regulations must be changed."
Defence experts say that although Taiwan can draw lessons from Ukraine's use of Starlink, a satellite network developed by Elon Musk's US-based space exploration company SpaceX, they worry about relying on a commercial actor with business interests in China.
"Elon Musk, we are not certain if he cares more about China's market," Tzeng said, referring to Tesla's sales in China. "We won't put all our eggs in one basket."
Taiwan does not own any Starlink terminals. SpaceX did not respond to a request for comment.
Taiwan is also strengthening the resilience of wartime communication channels for top commanders, including the president, according to one senior government official and another person familiar with government efforts.
"We are taking notes from Zelenskiy," a senior Taiwan security official said, referring to Ukrainian President Volodymyr Zelenskiy's strong presence on social media.
Taiwan's Ministry of Digital Affairs said in a statement that it would prioritise Taiwan's offshore islands for the satellite trial programme and would further increase the bandwidth for microwave communications with outlying islands by year-end. The ministry did not comment on sea cables or repairing them.
Securing undersea cables
Taiwan's vulnerability was thrown into focus last month when the two undersea cables connecting the Taiwan-controlled Matsu islands, which sit close to the Chinese coast, were cut, disconnecting the 14,000 people who live there from the internet.
Authorities said that their initial findings show a Chinese fishing vessel and a Chinese freighter caused the disruption, but that there was no evidence Beijing deliberately tampered with the cables. China's Taiwan Affairs Office did not immediately respond to a request for comment.
Chunghwa Telecom switched on a backup microwave system that transmits signals from the top of a mountain in Taipei to Matsu, but that only restored about 5 per cent of the bandwidth that the cables had provided.
This month, the government upgraded the system and internet speed significantly improved. But because there are few cable repair ships in the region, residents must wait until late April for internet access to be fully restored.
A senior Taiwan official familiar with security matters said that sea cable vulnerability has long been a national security concern, and that it was "ridiculous" so little progress had been made to address the issue. The person declined to be named because of the sensitivity of the matter.
"We can't even fix sea cables on our own," the official said.
Lii Wen, who leads the Matsu branch of the ruling Democratic Progressive Party, described the February outage as a "warning" to Taiwan. "Today, it's Matsu's sea cables that broke," he said. "What if one day all 14 of Taiwan's undersea cables connecting us to the outside world break? Will we be adequately prepared?"
China will probably take aim at Taiwan's sea cables or the cable landing stations before an all-out attack, experts say, a move that would cause panic, paralyse commercial activity, and help Beijing gain control over the international narrative.
China's Taiwan Affairs Office did not respond to a request for comment.
Taiwan's military has long prepared back-up plans, including a fibre-optic network for communications within Taiwan, satellites, high-frequency radio, and microwave systems.
The impact on civilians would be severe regardless, and authorities are reinforcing Taiwan's four entry points for international sea cables and running more frequent war simulations involving them, Huang said.
"In a state of emergency, people will want to get information," said Chieh Chung, a military researcher at the National Policy Foundation, a Taipei-based think tank. "If they can't get information, people's panic will spread."
Cutting off communications and causing chaos would not be the only military effects of severing the cables, Huang said. Taiwan might find it difficult to calibrate a response to such a move that an aggressor couldn't use to justify an all-out attack.
"So the first step (for China) - with about 99 percent likelihood - is to cut our sea cables," Huang said.