In 1884, during the Sino-French War, a fleet of heavily armed French warships advanced toward Taiwan’s Tamsui Harbor, only to be stopped by a series of naval mines and stone-laden boats. This unexpected obstacle thwarted the French from advancing to Taipei and led to their retreat after hours of fierce fighting on land. Today, Taiwan faces a different threat — China’s ambitions for invasion — yet the lessons from the Battle of Tamsui could still offer vital insights into modern defense strategy.
As Taiwan seeks ways to fortify its defenses, U.S. officials and Taiwanese strategists have championed the concept of Taiwan as a “porcupine,” bristling with numerous small, asymmetric capabilities. Surface-to-air missiles, drones, and mobile anti-ship missiles would form the backbone of this approach, aiming to deny China air superiority and create a “prickly fortress” in the sea. However, one tool has been largely overlooked in the discussions: naval mines. As RAND’s Scott Savitz points out, naval mines represent one of Taiwan’s most cost-effective and potent weapons for sea denial.
Strategically placed naval mines could allow Taiwan to exploit its natural geography and create an effective defense in depth. Taiwan’s shallow waters and challenging coastline would make it an ideal candidate for defensive mining, providing a low-cost, high-impact method to delay, disrupt, and degrade any Chinese invasion. Mines placed in key locations could channel Chinese forces into areas vulnerable to Taiwan’s other defenses, such as anti-ship missiles, drones, and coastal gun batteries, significantly slowing the enemy’s progress and inflicting costly attrition.
While sea mines aren’t a cure-all — they won’t help Taiwan fend off gray-zone activities or a full blockade — they can be a critical tool in delaying and disrupting the initial phases of a Chinese invasion. To unlock the full potential of mine warfare, Taiwan must make a serious investment in mines, minelayers, and training.
Taiwan’s Deterrence Strategy: Deny, Don’t Defend
The crux of Taiwan’s deterrence strategy lies in convincing China that it cannot achieve a quick, decisive victory. Taiwan’s strategy should aim for sea denial rather than sea control. While the People’s Liberation Army (PLA) requires sea control to launch a successful amphibious assault, Taiwan needs only to deny it. This strategy focuses on preventing China from gaining access to Taiwan’s littoral zones and impeding amphibious landings.
Taiwan’s western coastline offers a geographic advantage. The waters are shallow, ideal for mining, and Taiwan has relatively few landing beaches, most of which are narrow and difficult to access. This geography allows Taiwan to concentrate its mining efforts in key areas and impose significant costs on any Chinese attempt to invade.
Three Ways Mines Can Help Taiwan Deny a Chinese Invasion
Taiwan’s mine warfare strategy could function through three key mechanisms: delaying the invasion, disrupting the PLA’s plans, and degrading its forces.
1. Delay the Invasion
Mines can slow the arrival of Chinese forces, giving Taiwan’s military more time to organize a defense. A strategically placed minefield could delay a Chinese amphibious assault for days, forcing China to divert significant resources to minesweeping operations. By combining various mine types at different depths and locations, Taiwan could create a multi-layered defense that would slow down any attempt to clear a path to Taiwan’s shores. This tactic could take a page from history: during the Korean War, North Korea’s mining of Wonsan Harbor delayed a U.S. amphibious assault by several days, costing valuable time and causing significant frustration for the attackers.
2. Disrupt the Attack
Mines also offer Taiwan the ability to disrupt China’s highly choreographed invasion plans. The presence of mines would deny China the element of surprise and force the PLA to commit precious resources to clearing them. Mines can impede the movement of Chinese ships, especially when placed along narrow coastal approaches, forcing the invading fleet to alter course and disrupting the timing of its assault. The mere threat of mines can be enough to halt an entire operation, as the Germans learned during World War I when Russian mines forced them to abandon a planned naval operation in the Gulf of Riga.
3. Degrade the Enemy’s Forces
Naval mines can directly damage or sink Chinese ships, significantly degrading the PLA’s amphibious capabilities. Mines have historically been responsible for the loss of numerous ships, including several U.S. Navy vessels. Moreover, mines placed strategically in shallow waters or near critical landing zones can funnel Chinese forces into kill zones where they are vulnerable to Taiwan’s other weapons, such as anti-ship missiles and drones. This combined approach would increase the attrition rate of Chinese forces, ensuring that any invasion attempt comes at a steep cost.
Building a Mine Warfare Capability
While mines could significantly strengthen Taiwan’s defense, the island has not yet made the necessary investments. Taiwan’s current mine stockpile is small and outdated. To create a robust mining campaign, Taiwan would need to expand its mine stockpiles, focusing on a wide variety of mine types to create flexible, layered minefields. The priority should be acquiring cheap, easy-to-produce mines, such as moored contact mines or improvised “MacGyver mines.” These can cost as little as $2,000 each but have the potential to cause massive disruption when placed in shallow waters near key landing zones.
In addition to increasing its stockpiles, Taiwan must also develop the ability to lay mines quickly and covertly. It could use aircraft, surface vessels, or even civilian militia trained to deploy mines in strategic locations. Taiwan’s current fleet of minelayers could be expanded, and it could explore acquiring unmanned underwater vehicles designed for minelaying.
Training and Readiness
Taiwan must also improve its readiness for a large-scale mine warfare campaign. While small-scale minelaying drills have been conducted, Taiwan needs to make this training more intensive and realistic. A focused training program would prepare Taiwan’s air, naval, and coast guard forces to lay a wide array of mines quickly, potentially with the support of a civilian militia trained in minelaying operations.
Taiwan must also develop detailed plans for when and how to begin a protective mining campaign. With a Chinese invasion threat looming, Taiwan must decide in advance when to start laying mines, which areas to prioritize, and how to manage its mine stockpiles. Taiwan will need to balance this need for rapid action with the potential political fallout of laying mines too early, which could escalate tensions and lead to international criticism.
Conclusion: The Power of Naval Mines
As Taiwan faces the growing threat of Chinese aggression, naval mines offer an effective, low-cost tool for sea denial and defense. The lessons learned from past conflicts, like the Battle of Tamsui, highlight the value of mines as a potent defensive weapon. For Taiwan, integrating mine warfare into its broader defense strategy could prove critical in deterring Chinese aggression and buying precious time in the event of a crisis. By embracing this cost-effective tool, Taiwan can further fortify its “porcupine” defense and present a formidable challenge to any would-be invader.
