The First Job for NATO’s New Baltic Bloc

Sweden’s suddenly cleared path to NATO membership casts the Baltic Sea region in a new strategic light. For the first time in modern history, every state in the region except Russia will be part of a single, close-knit military alliance, which has led some to giddily declare the Baltic Sea a NATO lake. Other than the fate of Ukraine itself, the creation of a powerful northeastern bloc in NATO is the most strategically significant fallout for Europe from Russian President Vladimir Putin’s decision to go to war.

The Baltic region is also a crucible from which the answers to many of NATO’s most pressing questions could emerge. What does a coherent strategy for deterring Russia look like? How can the Baltic states best be defended? What capabilities are needed, and how will they be integrated across the alliance? The contributions of NATO’s newly unified Baltic bloc—the Nordics, the three Baltic states, Poland, and Germany—to European defense will be vital to the resilience of the alliance.

With NATO focused on supporting Ukraine and better securing the bloc’s eastern frontier, another vital effect of northeastern security cooperation is only now beginning to receive the attention it deserves. The region must urgently address two overlapping challenges: maritime infrastructure protection and energy security. Indeed, in addressing these vulnerabilities, the countries of the region could collectively strengthen security, become a laboratory for how to protect maritime infrastructure, and serve as a model for other regions to follow.

The Baltic Sea, just like the North Sea farther west, hosts a dense web of critical infrastructure links: ports and terminals, undersea pipelines, electricity transmission cables, and telecommunication cables. And their number is expected to grow: As the region completes a massive swing away from Russian energy, governments are expanding their liquefied natural gas (LNG) import infrastructure, building out offshore wind parks, and investing in new undersea power transmission lines. As the Baltic states accelerate their departure from the Russian power grid—a legacy from when they were annexed by the Soviet Union—they are making significant investments in power links with Europe. These and other investments will create an even denser network of critical infrastructure, particularly in an already crowded Baltic Sea.

Of course, Russia still maintains power projection capability, mainly through its naval, air, and missile bases in Kaliningrad—and unlike Russian land forces, these have not been gutted by the Kremlin’s war in Ukraine. The Russian Navy may be underfunded, but its underwater capabilities are growing in strength. Although the perpetrators have not been definitively determined, the underwater bombings of two Nord Stream pipelines near the Danish island of Bornholm in September 2022—as well as ongoing Russian threats and operations in the Baltic Sea and North Sea—have forced European governments to pay more attention to their highly vulnerable offshore energy and other infrastructure.

In recent months, NATO has ramped up Baltic Sea patrols and exercises and established a new Maritime Centre for the Security of Critical Undersea Infrastructure.

Accurately assessing threats to maritime energy and undersea communication infrastructure can be difficult. Adversaries could use submarines to deploy crewed or uncrewed submersibles, but attacks could also be launched from research vessels or even passing commercial ships. Also vulnerable to approach by sea are shoreline installations, such as LNG terminals. Landing stations for fiber-optic telecommunication cables are another possible target. What’s more, an adversary could easily employ civilian saboteurs to damage coastal infrastructure.

An attack need not be catastrophic—infrastructure networks usually have redundancies and extra capacity built in to compensate. Below the threshold of a blackout strike, however, infrastructure sabotage can be used by an adversary as a relatively easy and affordable way of sending a message or undermining a population’s sense of security. Sabotage could also prepare the ground for a broader attack. What makes sabotage attractive for an adversary is that attribution can be difficult, compounding the sense of insecurity and confusion. In January 2022, for instance, an undersea fiber-optic cable connecting a satellite ground station on the Norwegian island of Svalbard to the country’s mainland was severed, causing much speculation over Russian involvement. No conclusive evidence ever emerged. Meanwhile, NATO is certain that Russian spy ships have increased their efforts to map Europe’s critical maritime infrastructure.

Some of the larger countries in Europe are looking to step up their capacity to monitor, protect, and repair their undersea infrastructure. France has launched a new seabed warfare strategy and is investing in unmanned underwater vehicles, while Britain is creating a new Centre for Seabed Mapping and dedicating a multirole ocean surveillance ship to safeguarding infrastructure. Britain and Norway have also entered a security partnership to jointly protect their undersea infrastructure, a sign of London’s ambition to be a security provider in the region, including with regard to maritime energy and other infrastructure. (The two nations are major natural gas producers and have a network of pipelines crisscrossing the North Sea.) In the Baltic Sea, the Polish government is contemplating legislation that would permit the military to target ships attacking a key gas pipeline and establish a permanent coast guard base at the LNG terminal in the port of Swinoujscie. NATO already has a standing Maritime Group monitoring the North and Baltic seas and is conducting military exercises there. The Swedish submarine fleet will in future contribute greatly to NATO’s capabilities in the Baltic.

Most smaller European countries have only limited capacity to monitor and repair maritime infrastructure, even in their own waters. For all states, coordination remains a big challenge: Commercial owners and operators, militaries, coast guards, and other security services all have some responsibility in this field, as do policymakers and public administrators at various levels. While industry actors are often more aware of the immediate consequences of damaged energy or communication links, they rarely have access to comprehensive threat assessments compiled, if at all, by national governments. Then there is the issue of coordination across international borders. With so many actors involved, assembling a fully integrated operational picture of activity below and above water and developing contingency plans for responses to threats can be challenging, to say the least.

The Baltic Sea, with its shallow waters, low salinity, and many islands and archipelagoes, comes with some terrain-specific security challenges. Nevertheless, it is a useful testbed for how best to coordinate European responses to threats against critical maritime infrastructure. Both NATO and the European Union have turned their attention to shaping these responses and announced a new joint flagship initiative: the Task Force on Resilience of Critical Infrastructure. NATO-EU collaboration is a no-brainer here, since protecting critical maritime infrastructure requires merging military and civilian security measures. But both NATO and the EU will likely encounter obstacles working with so many different private actors and with sharing sensitive information about national infrastructure even among allies.

NATO can take the military lead. In recent months, it has ramped up patrols and naval exercises in the North Sea and Baltic Sea and established a new Maritime Centre for the Security of Critical Undersea Infrastructure within NATO’s Maritime Command. The bloc also wants to bring together national civilian, military, and industry stakeholders, doubling down on NATO’s role as a hub for sharing information and best practices. The alliance also plans to support members in identifying innovative technologies that can help secure critical undersea infrastructure. To underline the importance of all this, NATO leaders meeting in Vilnius, Lithuania, this week dedicated a whole paragraph of their official communique to the “real and … developing” threat to critical undersea infrastructure.

The EU updated its maritime strategy this year, stating its intention to ensure the resilience and protection of critical maritime infrastructure. A traditional starting point for the EU is to launch blocwide regulation, including a directive on critical infrastructure that entered into force this year. But the effectiveness of these measures depends on national capitals’ willingness to implement them effectively and quickly. The EU might get further if it is able to complement its regulatory stick with financial carrots, especially for smaller member states. Some of these states have asked for a dedicated section of the EU budget for public investments to protect critical infrastructure. The EU could also use its newly expanded tools on defense industrial funding to support member state investment in securing infrastructure.

Both organizations should also prepare for future threats to maritime infrastructure that may come not only from Russia. China, for instance, poses a different kind of security challenge as it buys and develops critical maritime infrastructure in Europe, from undersea communication cables to stakes in European ports. European governments have grown more alert to the potential risks of these investments in recent years, even as countries such as Germany continue to sign over infrastructure to Beijing. But officials tasked with tightening the investment review process complain that they do not yet have access to a clear map of who owns what in undersea and shoreline infrastructure.

In the years to come, the countries of the Baltic Sea region will be able to stress-test European responses to these challenges. Their efforts will likely yield valuable lessons for other operational theaters. These could include the Arctic, where melting ice could open up new sea routes for digital infrastructure. Partners of the West in the Indo-Pacific, facing similar hybrid threats to their critical maritime infrastructure, could learn from the European experience as well. Lessons from the region could also inform the EU’s plan to invest in a new undersea internet cable in the Black Sea designed to improve digital connections to Georgia, a candidate for EU membership, while reducing the country’s dependence on cables running through Russia.

The efforts to develop and implement a robust, shared approach to maritime infrastructure and energy security should include all countries in the Baltic Sea region, with the obvious exception of Russia. That may take some work, as these countries have not always seen eye to eye on security, especially in their assessment of Russia. Security in the northeastern bloc needs the buy-in of powerful Western European countries such as Germany. But the relationship between Berlin and Warsaw is increasingly deadlocked, preventing these two major countries from providing leadership in the region. Germany’s announcement that it will permanently station a military brigade in Lithuania, if it can be implemented quickly, could go some way to rebuild the trust lost by Berlin through its many years of Russia-friendly policies. The Polish elections in the fall, if they bring a change in government, might relax Warsaw’s relationship with the rest of Europe. A more strategic approach to regional security, however, will rely in large part on the military experience and innovation capacity of the smaller, nimbler Nordic and Baltic countries.

If NATO’s Baltic Sea members can build on Finnish and Swedish accession to the alliance, use all the tools at their disposal, and pursue a more coordinated, pragmatic approach to critical infrastructure security, they will reduce one of Europe’s greatest vulnerabilities exposed by Putin’s war on Ukraine. If NATO’s new northeastern bloc fails to achieve this despite a clear common threat and interest, there is little hope that the alliance can succeed elsewhere.