Officially redesignated from BBG(X) to BBGN, the 35,000-ton leviathan represents America’s first nuclear-powered surface combatant initiative since the Cold War era. Equipping USS Defiant with the A1B nuclear reactor addresses two major operational challenges simultaneously. Constrained shipyards The primary challenge facing the nuclear battleship program is not technology, but severe US supply chain challenges. A recent analysis stated that the United States relies on just two shipyards certified for naval nuclear construction, creating a significant issue for expanding the fleet. This vulnerability has prompted London to invest £1.7 billion to re-establish domestic enrichment and secure its long-term naval fuel independence.