From a leading Brookings Institution fellow and author of To Rule the Waves comes a vivid and bracing examination of today’s most secretive geopolitical conflict: the battle for dominance beneath the oceans.

Sub War explores a high-stakes, largely invisible race that is reshaping global power—a modern naval arms race unfolding in the deep. This is geopolitics at its most urgent: a strategic competition to control the undersea realm, a domain vital to global communications, international security, and the future of military and commercial technology.

Told in part from inside a US nuclear submarine—the most advanced war machine in modern history—Sub War traces how America is fighting to maintain its edge undersea while rivals like China and Russia work to close the gap. The book details the evolving landscape of submarine warfare and the rapid rise of UUVs (unmanned underwater vehicles), alongside new frontiers in deep-sea infrastructure: from new threats to transoceanic data cables to seabed mining and mapping to rare earth extraction.

It highlights how China views the undersea domain as both its greatest strategic vulnerability and a potential treasure trove of critical resources. Meanwhile, Russia is deploying advanced submarine designs to revive its geopolitical influence and threaten vital US and European infrastructure on the seabed. The Suez Canal, Taiwan Strait, and other international waters have become flashpoints in a submerged power rivalry.

At the same time, the crown jewels of the American economy—Silicon Valley tech giants, AI firms, and global finance—depend increasingly on vulnerable undersea networks. Yet US commercial and infrastructure policy has lagged, allowing China to expand its influence in strategic ocean corridors. China is also on the verge of lapping the US in vital ocean sciences.

From secret naval bases to deep-sea battle plans, Sub War is a gripping tour of the technological, economic, and military frontiers shaping the future of naval power. Essential reading for those interested in international relations, defense strategy, maritime issues, submarine innovation, and the new great game beneath the waves that could determine the future world order.