The Crucial Role of Submarine Cables in the Digital Age

By Fabrizio De Leonardis

The term “undersea infrastructure” refers to a complex network of “highways” stretching thousands of miles across the seafloor, carrying almost all the internet activities of multinational corporations. This is the world of submarine lines, which include power lines, canals, and optical data lines. It is estimated that there are over 500 active and planned lines worldwide, some of which can be quite short, while others extend up to 20,000 km.[i]

The geopolitical importance of submarine lines is largely significant for many countries, as they are essential to keep their economy going. Data represents the most applicable strategic asset of the 21st century, essential to the security and substance of nations and geographic areas.

Today, the internet is divided into technological spheres between the United States and China, while Europe seeks its sovereignty in the technological and digital spheres. Although digitization and technological invention take precedence in political agendas, it is surprising that an elemental aspect of the critical structure of global networks has received little strategic attention and exploration. This situation is worrisome, as the geopolitics of digital technologies, supply chains, and rising critical infrastructure is becoming less and less tied to the evolution of battles between Great Powers.[ii]

Moreover, the accelerated digital transition driven by the COVID epidemic and the arrival of advanced technologies like 5G are transforming societies into largely intertwined networks, placing submarine lines at the centre of profits and social development. These lines have become the subject of geopolitical competition among the world’s major powers as the internet, Wi-Fi, fibre optics, 5G, and satellite shipping have revolutionized global connections, and the importance of data protection is constantly growing.

In the first part of this article, we will explore the geopolitical importance of undersea networks, starting from the installation of the first undersea cable to the recent sabotage of major cables around the world. In the second part, NATO’s efforts to preserve submarine networks will be analysed, recognizing the Alliance’s crucial role in protecting critical infrastructure. Finally, the EU-NATO task force working in energy, transport, digital infrastructure, and space will be examined, highlighting the collaboration between the two entities to ensure security and resilience in critical infrastructure.

The geopolitical importance of submarine networks

In 1858, when the first submarine cable was installed, a transatlantic transmission could take up to 18 hours.[iii] Today, there are approximately 900,000 miles of submarine cables carrying data at speeds exceeding 25 terabytes per second, making data management extremely complex (see Figure 1).[iv] These cables are essential for the global telecommunications network, carrying over 95% of transcontinental internet traffic, including video calls, military operations, and supporting the global economy with financial transactions of around US $10 trillion per day. Their disruption could have significant impacts on communications between states or entire geographical areas.[v]

Figure 1 – Global Submarine Cables Map 2023

Source: TeleGeography, Submarine Cable Map, 2023 https://submarine-cable-map-2023.telegeography.com/

The war in Ukraine has reshaped the security landscape in Northern Europe, particularly in the Baltic and Arctic regions. In this context, the NATO Alliance has focused on providing support to Ukraine and strengthening its eastern flank. The recent accession of Sweden and Finland to NATO on March 7, 2024, and April 4, 2023, respectively, presents new opportunities to counter Russian aggression. The strategic significance of Sweden and Finland joining NATO is notable, given their longstanding policy of military neutrality.

The sabotage of the Nord Stream 1 and 2 gas pipelines in September 2022, followed by damage to the Baltic Connector gas pipeline and a data cable between Finland and Estonia in October 2023, allegedly caused by a ship’s anchor, has raised suspicions of deliberate attacks on critical infrastructure. While official attribution has not been confirmed, the events of last October have sparked significant interest among European politicians and the public regarding the underwater environment.[vi]

Furthermore, an incident in the Red Sea on February 24, 2024, which resulted in the damaging of four submarine cables (out of over fifteen in the Red Sea), led to a significant disruption in internet traffic between Asia and Europe, estimated at 25% according to data from HGC Global Communication in Hong Kong.[vii] Various hypotheses regarding the causes of these damages have been proposed. Israeli media have pointed to the Houthis, pro-Iranian Yemeni rebels, as the responsible party, attributing these actions to a gesture of solidarity toward the Palestinian people. On the other hand, U.S. sources suggest that the damage may have been caused by a missile attack by the Houthis on the ship Rubyma on February 18, during which the ship’s anchor could have damaged the submarine cables.[viii]

Despite differing hypotheses, it is evident that the incident in the Red Sea highlights the vulnerability of critical underwater infrastructure essential for connectivity and energy transport, underscoring the importance of ensuring the security of these vital networks. These attacks underscore the need to enhance the security of critical underwater infrastructure by implementing advanced protection measures and defence strategies to prevent future acts of sabotage. International cooperation and constant surveillance of submarine routes is essential to ensure security and stability in the region, especially in the context of increasing geopolitical tensions.

Furthermore, the protection of critical maritime infrastructure is an increasingly important security agenda considering the expansion of green offshore energy and digital infrastructures. This issue encompasses key geopolitical matters ranging from connectivity to security, regulation, and specific technical issues. However, most of these cables are not government-owned but managed by separate consortia of companies or private entities, lacking an international governance system or agency to regulate them. The legal ownership is divided among various co-owners within a complex system of jurisdictions, nationalities, conventions, and negotiations on international maritime law. When analysing the role of submarine cables, two fundamental dimensions must be considered.[ix]

Firstly, submarine cables that digitally connect the world are often overlooked and “invisible” to the public, akin to sewers. Yet, they are crucial for global infrastructure, interconnected with a myriad of other technological and social systems supporting planetary connectivity, from the cloud to internet providers. While in use for over 160 years, the submarine cable sector is undergoing significant transformation. While telecommunications companies previously dominated, tech giants like Google, Meta, Amazon, and Microsoft are now reshaping this ecosystem. The key difference lies in their business models: while telecom companies serve end customers, tech behemoths aim to maintain connectivity between their data centres and cloud services, often building their private submarine cable networks. This proliferation of wired paths is beneficial for global connectivity but also concentrates crucial infrastructure in the hands of a few major tech companies, which already dominate internet services, content, and markets. In 2022, these companies controlled about 66% of global submarine fibre optic capacity, compared to just 10% in 2012. This shift has implications for global security and the geography of the internet, increasingly centralized in a few nations and companies.

Secondly, the international legal regime governing submarine cables, dating back to the 1884 Convention and now part of the UN Convention on the Law of the Sea, is no longer adequate for today’s challenges.[x] Cables can be threatened by natural incidents, shark attacks, as well as hybrid warfare, terrorism, and belligerent actions by enemy states during wartime, which could cause severe economic and social disruptions. Yet, this regulatory regime is no longer at the forefront of intergovernmental cooperation.

In short, submarine cables, though invisible and taken for granted, are the physical foundation of an increasingly digitally connected world. As their control is shifting from telecommunications companies to tech giants and their geopolitical and security implications are becoming increasingly important, it is necessary to update the international legal framework to protect them.

NATO’s Efforts to Safeguard Undersea Critical Infrastructure

The protection of critical submarine infrastructure is a vital concern for NATO due to its significance in ensuring the security and defence of its member states. NATO has been working to improve the security of infrastructure for years, particularly after the attacks on the Nord Stream gas pipelines in September 2022 and the Baltic Connector in 2022. In response to these attacks, NATO has increased its military presence in the region, particularly in the Baltic Sea and the North Sea. During the Vilnius Summit in 2023, NATO established a Critical Submarine Infrastructure Coordination Cell in Brussels to identify vulnerabilities and improve information sharing between military and civilian authorities, as well as support engagement among allies, partners, and the private sector. This cell focused on creating a “community of trust” through meetings with leaders from the infrastructure sector.[xi] Furthermore, NATO leaders decided to establish a new Maritime Security Centre for Critical Submarine Infrastructure within the NATO Maritime Command (MARCOM) in the United Kingdom, as well as create a network operating among allies, the private sector, and relevant actors to improve information sharing and the exchange of best practices. This centre will have a broad range of tasks like the NATO Shipping Centre (NSC), which played a crucial role in NATO’s antipiracy operations. The new centre will also take over the responsibility of the Coordination Cell to facilitate the community of trust.[xii]

At the same time, as we will see in the next section, NATO is working with the European Union through the NATO-EU Task Force on Critical Infrastructure Resilience.

NATO’s maritime posture encompasses oceans and seas (including all elements present, above and below the surface, in all directions). Therefore, this area creates a continuum with other operational domains such as land, air, space, and cyberspace.[xiii]

NATO’s naval forces play a fundamental role on multiple fronts. Strategically, its mere presence generates deterrent effects and communicates the Alliance’s commitment to intervene when necessary. Due to their flexibility, these forces can be quickly deployed in configurations adapted to specific needs, offering a wide range of measured and achievable political and military options.

In terms of maritime security, naval forces contribute to maintaining a safe and protected environment through a wide range of operations and activities. Being ready and flexible, they can fulfil many missions and tasks in the realm of security.

In conflict, naval forces can rapidly transition from low-intensity operations to high-intensity missions. Their capabilities, spanning from the surface to the sub-surface, can be integrated to exercise control of the sea, deny it to the enemy, support the deployment of reinforcements, protect strategic assets, and project power, and support joint forces and effects.

In response to Russia’s large-scale invasion of Ukraine in February 2022, NATO activated its Gradual Response Plans and deployed elements of high readiness from the NATO Response Force (NRF) for the first time in a deterrent and defence role. This included the activation of Stationary Naval Forces, which are part of the NATO Response Force’s Very High Readiness Joint Task Force (VJTF). The VJTF was established in 2014 by the Allies during the Wales Summit and consists of about 20,000 units, including a multinational land brigade of about 5,000 troops and air, maritime, and Special Operations Forces components.[xiv]

NATO’s Naval Forces are composed of four groups: the NATO Maritime Groups (SNMG1 and SNMG2) and the Mine Countermeasures Groups (SNMCMG1 and SNMCMG2). All four groups are members of the NATO Response Force (NRF), which is part of the Alliance’s rapid deployment force, including the VJTF(M) and its maritime component. They operate in the Atlantic Ocean and the Baltic, North, Mediterranean, and Black Seas, covering the entire area of NATO’s maritime responsibility. Specifically, the NATO Maritime Groups SNMG1 and SNMG2 are subject to the authority of the Supreme Allied Commander in Europe (SACEUR). The NATO Maritime Command (MARCOM) has become the operational centre for all NATO maritime operations since December 2012. In this way, authority, and operational command over the SNMG are generally delegated to MARCOM. Located in the United Kingdom, MARCOM also hosts the NATO Shipping Centre (NSC), which is the main point of contact between NATO and the merchant shipping community. It is permanently managed by NATO and plays a significant role in countering piracy.[xv]

Since February 2022, NATO has increased its surveillance activities, including allied aircraft carriers in the Baltic, Adriatic, and Mediterranean seas and deploying additional Carrier Strike Groups. Indeed, NATO recognizes that the protection of critical maritime infrastructure requires better monitoring and surveillance—known as Maritime Domain Awareness (MDA)—and has launched a new technological initiative with Sweden in October 2023 to better integrate capabilities and explore how new technologies can improve MDA.[xvi]

The resolution of the NATO Parliamentary Assembly—founded in 1955 as an interparliamentary organization that brings together legislators from NATO member countries to discuss security and policy issues—of October 2023 emphasizes NATO’s commitment to strengthening and expanding these activities. The Alliance focuses on developing deterrent solutions, improving attribution through surveillance and information sharing with industry, and coordinating responses to incidents. Identifying vulnerable infrastructure and assessing the risk of attacks are crucial aspects. In the demanding submarine domain, Alliance structures will play a vital role, considering technical and military capabilities in submarine warfare, mine hunting, and special forces.[xvii]

However, the safeguarding of critical maritime infrastructure presents distinctions from other security endeavours, with the potential role of military forces being constrained. The spectrum of threats ranges from natural disasters and accidents to maritime crimes, terrorism, and state-sponsored sabotage in the Baltic Sea. Not all these threats necessarily require a military response but can depend on civilian resilience measures.

In a recent development, leading experts from across the Alliance met at NATO Headquarters on Thursday, 23 May 2024, for the inaugural meeting of NATO's new Critical Undersea Infrastructure Network. In response to escalating challenges to undersea infrastructure, the Alliance is implementing new tools to bolster the security of undersea cables and pipelines and to monitor potential threats. NATO has long cautioned about the security of undersea cables, prompting Allies to increase naval patrols near critical subsea infrastructure following recent incidents in the Baltic Sea. Secretary General Jens Stoltenberg, who inaugurated the conference, emphasized the need for continued efforts by Allies. Stoltenberg highlighted NATO's suitability to assume a greater role due to Allies' unique military capabilities, extensive intelligence network, and operational expertise, noting Russia's escalating hybrid campaign against Allies. During the meeting, participants deliberated on enhancing information-sharing, situational awareness, and strategies to deter and defend against threats to undersea infrastructure. Discussions included leveraging innovative technologies to fortify infrastructure security and resilience, particularly for the expanding number of offshore wind farms supporting the energy transition. The Alliance also advocated for technological innovation, such as sea drones, new sensors, and AI utilization, to enhance detection of suspicious activities.[xviii]

Finally, given the transnational nature of infrastructure, such as pipelines and cables connecting multiple countries, NATO member states know the need for close cooperation in surveillance, response, and investigations. Therefore, allies and partners maintain and develop capabilities through maritime exercises, build interoperability among their forces, and improve their overall abilities and readiness for all operations, national and international.

EU-NATO Task Force

The security of critical infrastructure is a topic of increasing importance for the European Union and NATO, especially in the context of Russia’s aggression against Ukraine. This conflict has introduced new risks, such as physical and cyber-attacks, often combined with hybrid threats. To address these threats, in March 2023, the EU and NATO strengthened their cooperation with the launch of the EU-NATO Working Group on the Resilience of Critical Infrastructure. The EU-NATO working group has identified four key cross-cutting sectors: energy, transportation, digital infrastructure, and space, which are crucial for the functioning of economies and societies.[xix]

The energy sector is particularly complex, as energy security is challenged by hostile actors operating in cyberspace, manipulating energy supplies, and using economic coercion. Critical energy infrastructure, such as gas pipelines and power grids, are vulnerable to sabotage and attacks, as demonstrated by recent events in Ukraine. The increasing reliance on renewable energies and electrification poses new challenges and opportunities for energy infrastructure. While diversification of energy sources and adoption of more sustainable technologies are ongoing, protecting infrastructure from cyber and physical attacks remains a priority. The specific characteristics of the energy sector, such as the need for real-time responses, the potential for cascading effects, and the coexistence of legacy and innovative technologies, require tailored strategies to ensure the resilience of energy infrastructures in an evolving environment.

Digital infrastructures, such as fibre optic cables and 5G networks, are vulnerable to accidental or intentional disruptions, posing risks to global networks and security. Digital infrastructure forms the fundamental basis for communications, which are essential for all social and economic functions. While redundancy is largely integrated into communication networks, it is important to plan for contingencies, identifying primary, alternative, emergency, and contingency requirements. Submarine communication cables are a crucial element of the global communication network, carrying 95% of global internet traffic. Given their length and the difficulty of monitoring them, they can be seen as an attractive target for an adversary. The vulnerability of submarine communication networks and 5G networks poses a significant risk to member states and allies, as repair capacity is limited globally, and repairs take time, especially for cables located in remote positions. 5G networks have become essential for many public services and economic functions, such as energy, transportation, banking, health, and industrial control systems. The dependence of these services on 5G networks and next-generation networks in the future would make the consequences of systemic and widespread disruption particularly severe.

The transportation sector is equally critical, as transport infrastructure, including airports and ports, are vulnerable to cyber-attacks that can cause economic damage and disruptions for military use. The increasing electrification of transportation leads to a greater dependence on the power grid, with implications for digital and energy infrastructure. The transportation infrastructure system plays a crucial role in protecting populations, economies, and armed forces. This vast system, comprising roads, railways, inland waterways, airports, seaports, and inland ports, can be publicly owned, privately owned, or the result of public-private partnerships. It is essential to maintain the functionality of transportation infrastructures, including those identified in the Trans-European Transport Network (TEN-T), which represents the main transport arteries in Europe and neighbouring countries.

The space sector is strategically relevant, as space infrastructures are subject to human and natural risks, with potential threats from strategic competitors that could compromise access and operations in space. Space assets may be owned and operated by the EU, member states, allies, and increasingly by commercial entities. Strategic competitors and potential adversaries are investing, developing, testing, and operationalizing sophisticated anti-space capabilities and doctrines that could threaten NATO and EU access and freedom of operation in space, compromise our defence, and harm our security.

In summary, the security of critical infrastructure is of great importance for the EU and NATO, as disruption to this could have devastating consequences for the economies, societies, and security of member states and allies. To address these threats, a holistic approach is needed that considers the complexity of interdependencies between different sectors and focuses on protecting infrastructures from cyber and physical attacks, as well as diversifying energy sources and ensuring redundancy in communication networks.

About the Author

Fabrizio De Leonardis completed a second-level master’s in Parliament and Public Policy from Luiss Guido Carli and majored in International Sciences and Diplomacy at the University of Bologna. He also participated in the Executive master’s in leadership for International Relations and Made in Italy offered by the Italy-USA Foundation after receiving the America Youth Award for University Talent. He holds a bachelor’s in Political Science and International Relations from the University of Messina. Currently, he is an analyst for the National Agency for Inward Investment and Economic Development and previously served as a research fellow in international economics at the Italian Trade Agency. Since May 2022, he has been a member of the Youth Council at the US Embassy in Rome and participated in the NATO Youth Summit 2023 as a US-Italy youth ambassador.

Notes

[i] “Threat to Undersea Infrastructure,” Cyfirma, April 2, 2024, https://www.cyfirma.com/blogs/threat-to-undersea-infrastructure/.

[ii] Raluca Csernatoni, “The Geopolitics of Submarine Cables, the Infrastructure of the Digital Age,” ISPI, June 22, 2022, https://www.ispionline.it/en/publication/geopolitics-submarine-cables-infrastructure-digital-age-35516.

[iii] Lieutenant (junior grade) Madison L. Long, “Information Warfare in the Depths: An Analysis of Global Undersea Cable Networks,” U.S. Naval Institute, Proceedings 149, no. 5 (May 2023): 1,443, https://www.usni.org/magazines/proceedings/2023/may/information-warfare-depths-analysis-global-undersea-cable-networks.

[iv] Robin Chataut, “Undersea cables are the unseen backbone of global internet,” The Conversation, April 1, 2024, https://theconversation.com/undersea-cables-are-the-unseen-backbone-of-the-global-internet-226300.

[v] Long, “Information Warfare in the Depths.”

[vi] Richard Milne, “Finland Investigates Potential Sabotage to Baltic Gas Pipeline,” Financial Times, October 10, 2023, https://www.ft.com/content/8d9baf58-22c2-4456-905c-15fd7f9dcd69.

[vii] “Statement - Supplementary Information of HGC Global Communications Regarding Submarine Cable Damage in the Red Sea To Demonstrate Hong Kong as International Telecommunication Hub,” HGC, March 4, 2024, https://www.hgc.com.hk/press-releases/statement-supplementary-information-of-hgc-global-communications-regarding-submarine-cable-damage-in-the-red-sea-to-demonstrate-hong-kong-as-international-telecommunication-hub-to-demonstrate-hong-kong-as-international-telecommunication-hub.

[viii] Eleanor Watson, “Ship sunk by Houthis likely responsible for damaging 3 telecommunications cables under Red Sea,” CBS News, March 6, 2024, https://www.cbsnews.com/news/houthis-ship-cutting-red-sea-telecommunications-cables/.

[ix] Csernatoni, “The Geopolitics of Submarine Cables.”

[x] Convention for the Protection of Submarine Telegraph Cables, Paris, March 14, 1884.

[xi] Christian Bueger, “NATO’s Contribution to Critical Maritime Infrastructure,” January 29, 2024, https://centerformaritimestrategy.org/publications/natos-contribution-to-critical-maritime-infrastructure-protection/.

[xii] Ibid.

[xiii] “NATO’s maritime activities,” NATO, last updated August 3, 2023, https://www.nato.int/cps/en/natohq/topics_70759.htm#posture.

[xiv] “NATO Response Force”, NATO, last updated 27 July, 2023, https://www.nato.int/cps/en/natolive/topics_49755.htm

[xv] “NATO PA Policy Recommendations,” NATO Parliamentary Assembly, October 9, 2023, https://www.nato-pa.int/document/2023-nato-pa-policy-recommendations.

[xvi] Bueger, “NATO’s Contribution to Critical.”

[xvii] NATO Parliamentary Assembly, “NATO PA Policy Recommendations.”

[xviii] “NATO holds first meeting of Critical Undersea Infrastructure Network,” NATO, last updated May, 23, 2024, https://www.nato.int/cps/en/natohq/news_225582.htm

[xix] “EU-NATO Task Force on the resilience of critical infrastructure: Final assessment report,” European Commission, June 29, 2023, https://commission.europa.eu/system/files/2023-06/EU-NATO_Final%20Assessment%20Report%20Digital.pdf.

Cover Image: https://www.nato.int/cps/en/natohq/news_225582.htm