European governments and militaries have placed their initial focus on Russia, given both the context of the war in Ukraine and a series of recent incidents linked back to the Kremlin. Russia has carried out underwater military exercises at depths below 6,000 meters, is “actively mapping” the critical undersea infrastructure of NATO members, and is increasing its activity over and around cables in the Baltic Sea. On multiple occasions, Russian vessels have also been known to be sailing near damaged European subsea data cables at the time of breakages. Several Western officials believe Russian intelligence agencies, not the Chinese government, were responsible for the damage from the most recent Baltic Sea cable cuts.

Lawmakers also worry about the possibility that both subsea cables themselves and the landing stations they connect to could be tapped by malign actors for espionage purposes. Officials in the United States and Europe have expressed concern over subsea data cables built and operated by China’s Huawei Marine Networks (HMN) Tech, citing cybersecurity and espionage risks.  The United States has pushed particularly hard to persuade third countries, including its European allies, to avoid installing cables owned by Chinese companies. Europeans have not always shared this risk assessment, highlighted by the installation of the Pakistan and East Africa Connecting Europe Cable, a 25,000-kilometer project operated by HMN Tech that connects Singapore to Marseilles, France, that became fully operational in December 2022. But China’s increasingly blatant support for Russia’s war and the involvement of Chinese-flagged vessels in the two Baltic Sea cable-cutting incidents, has led Europe to begin to consider China as a threat to European security, including its subsea cables.

Transatlantic cooperation on this issue is complicated by fierce competition between U.S. and European cable installation companies, as demand for new systems continues to skyrocket. This increase is largely driven by U.S.-based hyperscalers—large-scale cloud providers such as Google and Meta—not telecommunications firms, and Europe lacks a peer competitor to these tech giants. Yet both European and U.S. policymakers have an interest in their allies’ industry leaders succeeding in this space and should consider the establishment of joint venture and technology sharing agreements among U.S. and European cable firms.

Even before the October 2023 incident, NATO, the EU, and certain European governments began to increase their efforts to boost subsea cable resilience and security. In February 2023, NATO stood up a new Critical Undersea Infrastructure Coordination Cell in Brussels to convene stakeholders and enhance coordination between the public and private sectors. In July 2023, NATO allies at the Vilnius Summit established a Maritime Center for the Security of Critical Undersea Infrastructure as part of the alliance’s Maritime Command in Northwood, UK. In October 2023, after the first incident, NATO defense ministers endorsed a new Digital Ocean Vision, an initiative aimed at improving undersea surveillance. And in February 2024, the European Commission released its first “Recommendation on Secure and Resilient Submarine Cable Infrastructures,” encouraging member states to conduct regular stress tests, improve information sharing amongst themselves, and improve cable maintenance and repair capabilities.

Late last month at a summit of Nordic and Baltic leaders in Sweden, Polish Prime Minister Donald Tusk proposed a joint naval policing program among Baltic Sea countries to protect their undersea infrastructure against external security threats. This program would run parallel to a Baltic air policing mission already in place. But these states well know that any protective measures must be closely intertwined with deterrence—no military patrolling can cover all undersea infrastructure.

Some observers say that the most recent cable-cutting incident is proof that Europe’s efforts have failed. But differences in responses to the two incidents demonstrate the new seriousness with which these issues are being considered throughout Europe. In 2023, the NewNew Polar Bear continued sailing after damaging two subsea cables and a gas pipeline. The vessel ignored requests from Finnish and Estonian authorities to halt its voyage and returned to port in Tianjin, China. As of publication, Estonian authorities are still waiting on their Chinese counterparts to complete necessary procedures for Estonia to end its criminal investigation into the incident.