The Second World War was of epic proportions, and for the Western Allies, the triumph won was purchased on the strength of sea power. The contribution of navies stood first and foremost, in part, because their efforts allowed Allied armies and air forces to meet the Axis on terms of Allies’ choosing. At the forefront of this naval effort were the Royal Navy (RN) and the U.S. Navy (USN), supported by a host of other fleets, which first stemmed the enemies’ onslaught and then turned defeat into victory. To be sure, the Axis possessed their own means of sea power, but only the RN and the USN operated in all theaters of war while possessing the full spectrum of naval capabilities. It is these twin aspects that underpin Brian Lavery’s Two Navies Divided: The British and United States Navies in the Second World War.

The monograph’s title is a play on the tag that the English and Americans are two people separated by a common language. As the Continental Navy and the USN borrowed heavily from the practices of the RN when they were established, just assuredly as the English language itself morphed when transported to American shores, Lavery’s homage suggests a certain correctness. What follows is not a history so much as a comparative analysis of the two premier navies against the backdrop of their performance during the greatest conflict ever waged. Of course, given the ebb and flow of Allied fortunes, the performance of both navies proved uneven. Yet, more important, both nations and their navies adapted in a manner absent from their Axis rivals. Their ability to do so and the material dominance they eventually exhibited played no small part in the victory achieved in the ultimate sport of kings.

Although the RN and USN were nominally peer competitors in the interwar period, the RN benefited from a wealth of operational experience and possessed a global presence absent in the USN. Those strong cards, however, were insufficient for the war to come as the application of airpower increasingly came to dominate the maritime domain. The RN was alive to this—indeed, it had taken the lead in fashioning a naval air arm in the last war. That innovation, alas, was hamstrung in the years of peace owing to short finances, lack of vision, and the divided control present in its naval aviation. These failings were absent in the U.S. Navy and that the upstart supplanted the master as the ultimate arbiter in the maritime domain is largely the story of the exponential growth American fleet aviation enjoyed starting in 1942

Of course, the navies of the Second World War were more than the sum of their air forces, with the ability to execute amphibious operations increasingly the ultimate expression of maritime power. Again, the British had shown the way in the previous war. In this case, though, the example of Gallipoli seemingly demonstrated the perils of such ventures. This did not mean that the British ignored the subject but, as a satisfied power desiring to hold merely what it already possessed, the operational requirement to perfect such means was always lacking. Contrariwise, the USN and especially the U.S. Marine Corps recognized that fielding an amphibious capability was a sine qua non to any scheme of defense in the Pacific Ocean area where the probable enemy enjoyed the advantage of fixed positions. In war, no less than in law, possession is nine-tenths of the equation.

Though the RN and USN were outwardly near equals in 1939, their fortunes rapidly diverged as the industrial and financial resources underpinning the latter grew exponentially henceforth. While scale would come to define the USN more than tactical prowess, it still had to survive the battles of 1942 before its building program came to fruition. Here, the geographical isolation of the United States and the time bought by Britain in the European War allowed the USN to expand in a manner denied the RN. Ironically, both navies benefited from the industrial windfall as American types now largely re-equipped the Fleet Air Arm.

Two Navies Divided is excellent at covering the material and logistical foundations of the RN and USN. Insights abound, and the work is well illustrated with photographs, artwork, and tables. Lacking, however, is an analysis of the two navies’ doctrine for battle, their governing tactical precepts, and a discussion of the leadership offered by their principals. These omissions operate at the expense of the RN, which thought a great deal in the interwar period how to fight the next naval war based on its failings in the last and faced the challenge of meeting the European Axis while also trying to deter Japan. Many of the operational shortcomings Lavery notes about the RN, such as the need for its ships to operate over long ranges, had been identified in prewar exercises and staff studies. Funding to rectify such deficiencies, however, remained another matter, especially as the expansion of the Royal Air Force had priority from 1936.

Often the story presented is of the RN developing an initial capability only to see it expanded and perfected by the USN. All true, but increasingly as the USN came into its stride, the newer capabilities of maritime power would be born and perfected in the United States. This is more a story of the post-1945 period when guided missiles and atomic-powered warships appeared, but the phenomenon was becoming apparent even before then as the development of afloat logistics testifies. More than British ingenuity, the spur for such innovations was operational necessity which, until the United States entered the war, was largely lacking.

There are some omissions, doubtful assertions, and minor errors, but overall Lavery presents a valuable summary of the two principal navies, which together did so much to secure the defeat of the Axis. An example of a minor error is the assertion that the battleship HMS Nelson cost £56 million to build when in fact the entire Naval Estimates for 1927 did not even approach that sum. Six million in sterling would have been closer to the mark. And although poor cooperation between naval and military commanders was a feature in many prior British amphibious operations, this was the least of the problems experienced at Gallipoli in 1915, where poor strategy at the highest political level bedeviled events. Likewise, this reader takes exception to the belief that the outlook of senior American officers was broader than that of their British counterparts. A global empire, the sinews of worldwide trade, and the Imperial Defense College argue otherwise. Notwithstanding such complaints, Two Navies Divided remains a handsome piece of scholarship and is warmly recommended to all.