Information has become a crucial asset in a globalised world order, speed and consistent transmission of information have become vital for a thriving digital economy. To facilitate this global flow of information, subsea communication cables connect every continent in a vast network. Current estimates suggest subsea cables transmit more than 95% of internet traffic, facilitating USD $10 trillion in financial transactions every day in the US financial sector alone (Brock, 2023; Goodman & Wayland, 2022). Additional research has stressed an increased cable manufacturing effort by several nation states, coupled with tense bidding for cable project contracts and the designation of placements, which disrupt the interests of other parties (Noor, 2024, p. 7-8). Arguably, this tense situation opens a new dimension to the ongoing security dilemma between regional superpowers in Southeast Asia, with uncertain and perhaps harmful outcomes. The fragility of these cables with their vital communication and electricity transmission capacity, will leave them as exposed desirable targets in conflict scenarios. I will additionally analyse two factors to consider from a global competition context: market driven interests and state driven interests.
Figure 1: number of subsea cable suppliers in SEA (Dec 2024)
Subsea cable networks have expanded considerably since the late 1990s. The introduction of the South East Asia – Middle East – Western Europe (SEA-ME-WE) 3 (1999) and 4 (2005) cables were major achievements in connecting SEA with financial sectors to the West, brought about by market driven consortium efforts from countries along their route (Noor, 2024, p. 2). In recent years, the demand for cables has grown exponentially with the reliance on global digital connection. However, the supply has been strained, especially in SEA, due to lengthy production times, limited number of manufacturing facilities, and ongoing repair work (ASEAN Centre for Energy & USAID, 2025. P. 28). Regional powers in SEA have become highly aware of this imbalance in supply and demand, with investment increasing in a multipolar instead of monopolar trajectory. As figure 1 clearly depicts 4 nation states with company stakes in cable projects, reflecting a multipolar spread of influence thus far (Won, 2025). Although a monopolar system has the benefit of security, a multipolar model relies on a diverse range of suppliers contributing in a competitive climate. This push for cable security under a monopoly has motivated at least two nation states in global contention: the US and China.
Both the US and China have significantly invested into the cable infrastructure of SEA and the South China Sea, as part of a wider contest over influence in the region. As has become evident in politically motivated cable projects currently under construction throughout SEA. These include the US funded Asia connect cable (ACC) and China funded Asia Direct Cable (ADC), both being manufactured by state-affiliated companies, who aim to facilitate the everyday intercontinental flow of data and ensure their own connection security. For China, subsea cable policy has been at the forefront of recent initiatives in SEA and the South China Sea. The partial nationalisation of HMN technologies has seen the Chinese cable manufacturer become the most promising in the past decade (Brock, 2023). US and China influence has been exposed before in 2022 during the SEA-ME-WE 6 contract bidding, where a US based company won the bid through diplomatic pressure and attractive training grants (Won, 2025). This resulted in China’s more proactive stance in the SEA region, as seen in their record completion time of the ADC (Sweeting, 2025). Bidding wars over contracts such as SEA-ME-WE 6 are only rising for these intercontinental subsea cables, meaning a security dilemma over marine infrastructure has already developed its first symptoms.
The fragility of these cables is another recurring issue, especially in SEA where natural disasters occur often. The ring of fire alone has been responsible for multiple internet cable cuts with the whole of Tonga losing connection following a volcanic eruption for over a month. Resulting in a freeze of recovery efforts and local finance (Yerushalmy, 2024). Further obstruction of cable repairs occurs by jurisdictions from states with poor marine infrastructure legislation and some of the most frequented trawler and freight routes on the planet. Subsea cable support is particularly limited in Indonesia, since breakages occur often in the trade congested Malacca and Sunda straits. In addition, Indonesia’s strict cabotage laws only allow repairs using domestic ships and repairmen, extending repair times by months for tedious maritime security purposes (Haddon, 2024).
The complexity of cable security is also attributed to a lack of surveillance, which remains extremely difficult, in situations where damage may be deliberate. If there is no proof of deliberate sabotage or an action is labelled an accident, repercussions will appear overblown. This grey zone tactic has been employed by China in the South China Sea on cables connected to Taiwan (Rahman, 2024). Furthermore, Reports of a specialised repair and sabotage ship with cable depth reach of up to 4000m have also been circulated since early 2025 (Murphy & Pearl, 2025). International legislation for the protection of undersea cables has undergone little development due to this lack of surveillance. Only NGOs such as the International Cable Protection Committee (ICPC) either promote protection guidelines or advise contracts and state interests.
This situation has been observed closely by SEA countries, with ASEAN bolstering subsea cable redundancy through the Quad Partnership for Cable Connectivity and Resilience and other technical knowledge-sharing initiatives (Hourn, 2025). Cable redundancy, connecting more cables to a state or island, appears the quicker fix in a region where cable damages are relentless, no matter the expense. Fortunately, ‘minilateral’ agreements with the US and its allies has provided substantial funding in the Indo-Pacific to counter Chinese investment and potential leverage over marine infrastructure (Won, 2025). Thus, funding from both the US and China has reinforced regional redundancy, especially in the Indo-Pacific.
The most recent developments in subsea cable protection are found on the other side of the world in Denmark, where suspected cable sabotage by Russia has plagued the Baltic Sea since the Russo-Ukrainian war began. Danish armed forces have deployed California-based ‘saildrones’ along crucial shipping and pipeline routes, utilising AI to compile surveillance on maritime activity occurring from a ground perspective, rather than the disconnect of a satellite (Bryant, 2025). Moreover, drone specialists from Danish universities are currently developing the U-SHIELD system, a fleet of underwater drones capable of immobilising security threats to marine infrastructure, such as pipelines and wind farms necessary for Denmark’s sustainable energy transition (Innovation Fund Denmark, 2025). These developments in Denmark must be replicated in other parts of the world, ensuring a dependable security and surveillance system for marine infrastructure.
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About the author:
Cameron Regan was an international intern at CESASS UGM through the Flexible Language Immersion Program (FLIP) at Acicis. Currently, he is pursuing his studies in International Relations at the University of Queensland, Australia.