Underwater infrastructure has become a key hybrid warfare battlefield with nations investing billions in advanced technologies like AI-driven underwater drones, quantum sensors, and integrated sensor networks to protect critical undersea cables and pipelines from sabotage, amid rising geopolitical tensions and recent incidents involving Russian proxy forces.

The article discusses the emergence of the underwater domain as a strategic and geopolitical battlefield crucial for hybrid warfare. It highlights that more than 99% of global data traffic travels via undersea cables and energy supplies depend on underwater gas and power pipelines, making these infrastructures critical and vulnerable to sabotage. It mentions the market for underwater defense technologies, estimated at around 50 billion euros annually, focusing on advanced systems like Italy's DEEP system that employs sensor arrays and autonomous underwater drone swarms with AI for real-time threat detection and risk mitigation. The article notes recent sabotage attempts linked to Russian proxy fleets, underscoring the elevated threat level to maritime commerce and infrastructure. It also covers innovations such as Distributed Acoustic Sensing (DAS) turning fiber optic cables into hydrophones, quantum magnetometers detecting submarine hulls, and the push for interoperable European underwater wireless communications to create a shared NATO maritime situational awareness. There is a geopolitical risk of a digital 'decoupling' with Western and Chinese-dominated underwater cable networks.