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Control over the seabed has become a vital strategic component of maritime security due to the increased global reliance on critical underwater infrastructure, such as gas pipelines and data cables. However, the underwater domain presents significant challenges, including limited transparency and technical complexity, which often result in ”sea-blindness”. Traditional naval theories are primarily developed for surface operations; therefore, they face uncertainty regarding their applicability to this increasingly complex operational environment. 

This thesis tests the explanatory power of Milan Vego’s theory of sea control in the context of seabed control during incidents of sabotage. Specifically, it examines the hypothesis that higher capabilities in terms of resources, cooperation, and situational awareness lead to a higher degree of seabed control. Using a theory-testing qualitative comparative case study with a ”most-similar” design, the analysis focuses on two incidents in the Baltic Sea: the Nord Stream sabotage (2022) and the C-Lion1 incident (2024). The analysis is structured around Vego’s four mechanisms: destruction of enemy forces, binding, control of strategic areas, and control of key terrain. 

The results indicate that traditional sea control theory explains seabed control primarily in a reactive rather than a proactive capacity. While capabilities were insufficient to prevent the initial sabotage in both cases, the C-Lion1 incident demonstrates that higher levels of international cooperation and situational awareness enable actors to re-establish limited control and restrict an adversary’s freedom of action after the incident. The study concludes that seabed control remains shaped by a highly complex and constrained operational environment and recommends that future military doctrines and maritime strategies incorporate autonomous underwater systems and civil resilience to address these structural challenges.