Thwarting Communications Blackout

The prospect of more cable cuts looms large, and Taiwan has taken steps to address several dimensions of the problem and provide new response options. Together, these initiatives aim to harden cable infrastructure, strengthen legal frameworks, improve monitoring, and field capabilities that demonstrate Taiwan’s political will to act while avoiding uncontrolled escalation.

The ultimate impact of any undersea cable attack depends on scale and location. China cannot cut off Taiwan from the global internet unless PRC forces cut through all of Taiwan’s cables, although severing any of them reduces bandwidth and increases latency. Beijing might be restrained, however, from going too far by its desire to preserve some connectivity as a pathway through which to transmit cyberattacks and disinformation.

Next, Taiwan is looking to a portfolio of satellite constellations to provide backup communication options in case China cuts Taiwan’s cables. But political and regulatory hurdles prevent Taiwan from relying on the dominant provider, Starlink. Commercial and indigenous alternatives are progressing, but they still have a long way to go to achieve sufficient size. A functional backup also requires access to ground stations and provider-specific terminals on the user end.

Even if a full-scale satellite communication system is in place, undersea cables will continue to outstrip satellite bandwidth by several orders of magnitude, underscoring that satellites can only supplement, not replace, Taiwan’s undersea cables. In a crisis, China would likely target communication satellites in a variety of ways, but Beijing might choose restraint given the escalatory potential and its own reliance on space-based infrastructure.

Finally, China will increasingly contest the electromagnetic spectrum using electronic warfare (EW) techniques. EW takes many forms but generally falls into three categories of support, attack, and protection. In prior eras, EW was primarily a tool for narrow tactical tasks such as defending aircraft against missile attacks. Today, EW shapes the entire battlefield and is much more intricate and dynamic. EW attacks can target navigation systems, such as GPS; radars for monitoring airspace; and communication networks, including the satellite communication systems discussed earlier.

To date, China has not yet conducted EW attack operations at a significant scale to pressure Taiwan. But Beijing has used EW in other areas, such as the South China Sea, and is gleaning new operational insights from recent conflicts, especially Russian fighting in Ukraine. In the future, China could ramp up EW pressure on Taiwan through targeted operations designed to harass and interfere with specific aircraft or places, such as critical ports or cable landing stations.

The United States, Taiwan, and other like-minded partners should take action across the following three categories to better protect Taiwan’s information and communication networks and thwart any future communications blackout.

Undersea Cables

• Taiwan should consider mandating that new or repaired cable projects use physical hardening measures to make them more difficult to interfere with.
• The United States and Taiwan should deepen cooperation on maritime intelligence and monitoring.
• The United States should compile a dataset documenting cable-cutting incidents and, where intelligence supports this conclusion, formally attribute sabotage incidents.
• Taiwan should continue to enhance maritime law enforcement and response in line with its recent legal and regulatory revisions and ensuing changes to practice.

Satellite Communications

• The United States should clarify and, where needed, amend, applicable laws and regulations to ensure that companies that sell defense services to the U.S. government, and have an agreement with an ally or partner to provide such services, can be compelled by the U.S. government to continue to serve such ally or partner, under critical circumstances and in accordance with U.S. national security interests.
• Washington should support Taipei’s efforts to develop a non-Starlink option for satellite communications.
• The United States and Taiwan should, as part of their occasional high-level, unofficial consultation and planning meetings, develop a plan for how to manage internet bandwidth during a situation where China (or any other actor) disrupts service from Taiwan’s undersea cables.
• Washington and Taipei should continually monitor technological breakthroughs and maturation in satellite communications.

Electronic Warfare

• Taiwan should leverage its growing relationships with European countries, particularly the Nordic and Baltic states, to learn about their experiences with and responses to Russian EW activities interfering with both civilian and military operations.
• Taiwan should conduct an exercise with civilian aviation and maritime authorities to practice operating under conditions where satellite navigation services are disrupted.
• Washington and Taipei should study the viability for both civilian and military applications of creative workarounds, such as enabling key systems to use China’s global navigation satellite system, BeiDou, or Russia’s Global Navigation Satellite System (GLONASS).
• Both the U.S. and Taiwan militaries need to prepare for, and practice operating in, an environment where capabilities that depend on the electromagnetic spectrum to function will be severely degraded, if not outright denied.
• The United States and Taiwan should jointly develop plans to go on EW offense against Chinese forces in a contingency.

Introduction

Control over the physical means of transmitting information—the lifeblood of modern societies—has become a central area of contestation between Taiwan (formally, the Republic of China or ROC) and the United States on one side, and China (formally, the People’s Republic of China or PRC) on the other. Whichever side gains the upper hand in this struggle will enjoy tactical and operational advantage—and could even decide strategic-level outcomes for the security environment across the Taiwan Strait.

Both Beijing and Taipei view information and communication networks as vital, perhaps decisive, aspects of a cross-Strait contest. At some point in the future, China might try to assert physical control (as opposed to cyber control) over Taiwan’s information environment. Beijing could even try to create a communications blackout or information blockade of Taiwan. In doing so, China would seek to impede government and military communications about how to respond and sow confusion and fear among Taiwan’s citizens.

Beijing could also try to block Taiwan’s leadership from making an appeal for help to the outside world. China has watched closely how Russia’s inability to cut off Ukraine’s communications has allowed Kyiv to rally domestic and international support for its defense. Taiwan’s civilian and military leaders understand Beijing’s views and intentions. In response, Taipei has developed a plan to prevent and respond to—and thereby deter—China’s attempts at imposing a communications blackout. The plan, known as Whole-of-Society Defense Resilience, lists protecting information networks as one of its five pillars.¹

This report explores three areas that would be decisive in the battle for information control across the Taiwan Strait: undersea cables, satellite communication systems, and the electromagnetic spectrum. In each of these areas, China is on offense, while Taiwan, along with the United States and other partners, is on defense. But both Beijing and Taipei are taking the initiative, resulting in a complex game of measure and countermeasure that spans civilian and military domains.

The text proceeds in four parts. First, it explores the role of the undersea cables through which Taiwan communicates with the outside world. Then, the report considers satellite communication systems that could provide a backup to undersea cables. Third, it looks at the electromagnetic spectrum and efforts to control or deny it through electronic warfare (EW). The report concludes with recommendations for policymakers in Washington and Taipei as they work to uphold peace and stability across the Taiwan Strait and thwart Beijing’s attempts to assert control over Taiwan through coercion or force.

The analysis delves into the specifics of each area to explain how technical attributes shape their geopolitical contours. In doing so, it aims to inform broad policy conversations with critical context that might otherwise be confined to niche technical discussions. The report explores these central topics as they play out in the gray zone between peace and war, as well as how they might unfold during a higher-level crisis on the escalation ladder toward all-out war.² Using this approach avoids linking the report’s analysis too closely with any one of many possible future scenarios at the expense of others.

Finally, a note about the report’s scope: China’s overall conception of the role of information in warfare extends beyond physical control over the means of transmitting information to include cyber warfare and so-called cognitive warfare. The latter is a catchall term for psychological warfare, disinformation, and misinformation. The authors chose not to address the latter topics in this report due to length restrictions and because they are well covered elsewhere.