Undersea War

How sabotage and disorder threaten the fragile network of undersea cables and pipelines that makes modern life possible—and how it may already be drawing the world into an all-out underwater war.

The world depends on a tangle of underwater tubes on the ocean floor. Every day undersea cables transmit nearly all the world’s data, while intercontinental pipelines convey two-thirds of the world’s oil and gas. They do their jobs so reliably that few would guess that “the cloud” is actually underwater, or that global economic stability relies on pipelines on the seafloor. But as award-winning security expert Elisabeth Braw reveals, an invisible battle over those cables and pipelines is ramping up.

Undersea War tells the story of the underwater infrastructure that supports everyday life. In 2022, after decades of seeming undersea harmony, two pipelines in the Baltic Sea mysteriously exploded. Within months, the cutting of the data links between Taiwan’s Matsu Islands’ and the world along with the the subsequent destruction of additional Baltic cables and a pipeline signaled that the harmony in the ocean depths was over. Superpowers are now racing to protect themselves as the seabed itself becomes a battlefield.

Blending engrossing historical narrative with acute strategic analysis, Undersea War shows that the next battle for global supremacy may unfold on the ocean floor.

• “A masterful and compelling book by one of the most insightful observers of modern strategic competition. Elisabeth Braw illuminates brilliantly the hidden undersea networks that underpin the global economy and explains why they have become a critical frontier of international competition. Timely, authoritative, and highly relevant, Undersea War is essential reading for policymakers, business leaders, and citizens alike.” 
  General David Petraeus, US Army, retired, coauthor of the New York Times bestseller Conflict
• “The definitive account of one of the least understood dimensions of great power competition of the twenty-first century. In Undersea War, Elisabeth Braw combines meticulous research with lively prose to tell the story of choke points of cable and pipelines in the oceans that must concern all international security experts.”
  Michael McFaul, author of Autocrats vs. Democrats
• “Elisabeth Braw tells one of the most important and yet mostly unknown security stories existing today. As she lays out in meticulous detail, much of modern life is dependent on a network of undersea cables and pipelines that link the globe together. While vital, as the last few years have made depressingly clear, these connections are also extremely vulnerable to damage and even outright destruction. In bringing this issue out with clarity and purpose, Braw has done a great service and told a brilliant story. A must-read.”
  Phillips Payson O’Brien, author of War and Power
• “The cloud is not in the sky—it is in the sea. The cables and pipelines resting on the ocean floor carry the electricity, energy, data, and communications that modern societies depend upon. And they are under attack. In Undersea War, Elisabeth Braw reveals how hostile actors linked to Russia and China—using shadow fleets, disguised vessels, and deliberately dropped anchors—are targeting this critical infrastructure. These acts fall below the threshold of war, yet threaten economies, security, and daily life. It is grey-zone conflict: coercion without confrontation. As the rules-based order weakens, so too do the conventions that protect the seabed. Who is responsible for defending the infrastructure on which civilization depends? And how can democracies deter those who sabotage it? Timely, authoritative, and deeply unsettling, Undersea War illuminates one of the most consequential—and least understood—security challenges of our age.”
  Emma Sky, author of The Unraveling