Companies and governments are turning attention to the ocean floor as a new domain of warfare, driven by the vulnerability of subsea communications cables, energy pipelines and power links that underpin the global economy. More than 1.5 million kilometers of submarine communications cables were in service worldwide as of early 2026, according to TeleGeography. The 2022 sabotage of the Nord Stream gas pipelines in the Baltic Sea, along with other incidents near the Arctic and Taiwan, has highlighted long‑neglected risks, said Katja Bego, senior research fellow at Chatham House.
Advances in artificial intelligence, drones and autonomous technology are enabling new approaches to underwater surveillance. Defense contractors are positioning themselves for this shift. Italian shipbuilder Fincantieri announced in July a plan to acquire majority stakes in four companies for about 600 million euros ($689 million) to expand its capabilities in underwater and surface drones, marine surveying and subsea communications. CEO Pierroberto Folgiero described underwater telecommunications as "the real enabler" of an emerging ecosystem that could see surface ships act as motherships for fleets of autonomous vehicles.
France’s Thales has also built businesses covering sonar, anti‑submarine warfare, mine detection and autonomous underwater systems. Meanwhile, Germany‑based Euroatlas has developed the GrayShark autonomous underwater vehicle, which can operate on pre‑programmed missions and report anomalies such as mine‑like objects for operator review. Euroatlas says it has signed contracts worth more than 100 million euros with unnamed European navies for GrayShark and is working on a hydrogen fuel‑cell variant intended to operate for up to 16 weeks or 8,000 nautical miles, though that endurance has not yet been demonstrated.
Experts note that crewed ships and submarines cannot continuously patrol vast seabed areas, making a mix of manned and autonomous systems necessary. Euroatlas chief strategy officer Verineia Codrean said the goal is not to replace conventional platforms but to increase drone‑on‑drone activity, with manned assets stepping in when needed. The emerging market is prompting navies to focus on interoperability between crewed and unmanned systems.
The developments come amid broader hybrid‑warfare concerns that blend cyberattacks, energy sabotage, disinformation and economic pressure, with or without conventional military action.
