Phillips Payson O’Brien, How the War Was Won: Air-Sea Power and Allied Victory in World War II (Cambridge: Cambridge University Press, 2015).
Phillips Payson O’Brien opens How the War was Won with a provocative statement: “There were no decisive battles in World War II” (2). What he means by this assertion is that World War II was not won at so-called “decisive” battles like El Alamein, Kursk, or Midway. Rather, what really proved decisive was the attrition waged on what he terms “super-battlefields” (e.g. the Atlantic Ocean or the skies of Germany) in which each side employed primarily air and sea power to destroy enemy equipment in pre-production, production, and deployment (5). This book is not a history of World War II; it looks at one very important aspect of the war, the production and destruction of military equipment, and draws significant conclusions regarding strategy and the way the Western Allies won the war. As the subtitle suggests, massive investments in air and sea power yielded enormous dividends and played a huge role in destroying the Axis powers. As O’Brien puts it,
The struggle throughout the air-sea super-battlefield determined the outcome of every land battle in the war. In the first case it determined the vast majority of World War II munitions production. It then, limited, in some cases most severely, the types of each weapon that could be built, and just as important, the amount of built equipment that was able to reach the fighting area. Finally, when it came to the land battles, the ability to control or deny control of the air space over the fighting almost always proved decisive (6).
Before the war, although most powers had only the haziest notion of how they would use air and sea power, they instinctively understood that that they had to manufacture large numbers of aircraft and naval vessels. In the United States, this commitment to air and sea power was also driven by interservice rivalry. The machinations of Admiral Ernest King, commander-in-chief of the US fleet and chief of naval operations, proved decisive in obtaining an enormous amount of material for his branch of the service (and not only making a mockery of the so-called “Germany first” strategy but also ensuring that the US Navy would be able to mount its own drive in the central Pacific independent of the army’s offensive in the southern Pacific). By 1944, the US Navy’s air arm was slightly larger than the Luftwaffe and only smaller than the RAF and the USAAF. In any event, among all the belligerents, according to O’Brien, the proportion of productive capacity devoted particularly to air forces is staggering. For example, after surveying the statistics, he judges that in July 1944, the month that German munitions production reached its zenith, well over half of armaments and ammunition output went to the Luftwaffe and over two-thirds was devoured by the German air force and navy combined (27). If anything, the proportions for Great Britain, the United States, and Japan were even higher. Indeed, the United States devoted so much industrial might to air and sea forces that these commitments were a primary consideration in limiting the army to 100 divisions.
This investment in air and sea power, O’Brien argues, was warranted. For sure, enemy weaponry could be wrecked on the battlefield. However, aircraft and naval vessels could deny to the enemy the resources necessary to build this weaponry; wreck the facilities where this weaponry was constructed; and smash this weaponry as it traveled to the battlefield. This is exactly what the British and the Americans sought to do with increasing success as the war dragged on. Germany and Japan could have coped with their battlefield losses of tanks, artillery, and so on. To cite just one statistic (the book is full of startling figures), between July and August 1943, that is, during the Battle of Kursk, widely considered an especially destructive battle, the Germans lost 1,331 armored fighting vehicles on the entire Eastern Front; such a figure only represented about 11% of such vehicles produced by Germany that year. Far more serious were the losses of weaponry (particularly aircraft) and fighting strength lost off the traditional battlefield
O’Brien focuses on three strategic initiatives: the Battle of the Atlantic, the Anglo-American Combined Bombing Offensive (CBO) against Germany, and the US Navy’s drive against the Mariana archipelago. Each required an enormous amount of equipment, and each, he argues, proved decisive. As O’Brien puts it, “any discussion of the air-sea victory of the United States and the United Kingdom must start with control of the movement of supplies and raw materials across the Atlantic Ocean” (232). The stakes were high for both sides. While the Arsenal of Democracy was not vulnerable to German bombing (unlike German industry which was susceptible to Allied air attack), its products were exposed to German assault as they passed across the Atlantic to Britain. If the Germans could have prevented enough supplies from crossing the ocean, they could have prevented the build up of Anglo-American force in Britain, turned on the Soviets (whose productive power was inferior), and won the war in Europe. As O’Brien argues (and this type of argument appears throughout the book), even if the Germans had no hope of winning the Battle of the Atlantic, their substantial investment in U-boats made a great deal of sense. First, it allowed them to destroy an enormous amount of American equipment before it ever reached Europe. O’Brien calculates that by sinking over 20% of the bauxite (the ore used to make aluminum) that the United States attempted to ship to Britain in 1942, the Germany navy destroyed more Allied aircraft in pre-production than the Luftwaffe shot down in combat between 1942 and 1943. At the same time, U-boats also destroyed more American army equipment in transit than the Germany army did on the battlefield in 1942. Second, the U-boat offensive compelled the British and the Americans to spend billions of dollars on merchants and escort vessels—money could have been devoted to something else. Third, it led to the diversion of Allied strategic air power (in 1943, half of the bombs dropped by American strategic forces and one-fifth of those dropped by the British were placed on German submarine targets). In this battle of material and technology, however, the Allies had the advantage. As O’Brien argues, “Victory for the Allies was made possible by the British pushing the boundaries of modern warfare fully. It required technological superiority, for example with radar and sonar, superb operational analysis of the science of convoy speed and size, great shipbuilding resources, excellent training, and, eventually, a significant air component” (230). Allied victory on “superbattlefield” of the Atlantic “marked the end of any possibility for Germany to win the war” (230).
Many readers may not be particularly surprised by O’Brien’s narrative of the Battle of the Atlantic (although his quantification of the Allied effort certainly does put matters in perspective), but his attempt to rehabilitate the CBO will probably prove much more controversial. A number of prominent historians have characterized the Allied strategic bombing of Germany as ineffective and immoral (for an especially prominent example, see the review of Richard Overy’s Bombing War). O’Brien starts from the premise that the RAF’s strategy of laying entire German cities to waste was unproductive but that the USAAF’s targeting of key industries exerted a much greater impact (other scholars, and Overy again is a good example, do not see much of a distinction between the two air forces in practice). O’Brien concedes that the Allied strategic bombing campaign of 1943 was a failure. However, he argues that as the air forces of the Western Allies adjustrf (particularly the United States) and brought more force to bear on Germany, they eventually made an enormous contribution in 1944 and 1945 to the collapse of Nazi military power.
O’Brien argues that American bombing, which targeted aircraft manufacturing (particularly fighters), hydrogenation plans, ball-bearing production, and eventually transportation networks, had far-reaching consequences for Germany. Such bombing destroyed a number of aircraft before they ever became operational and compelled the Germans to disperse their aircraft industry, leading to greater inefficiency and lower quality manufacturing. The bombings also effected momentous changes to the allocation of resources (that is, when resources could still be allocated, for the bombing of the transportation network eventually brought the German economy to a standstill when factories could no longer obtain coal or raw materials). A large amount of German labor was shifted from manufacturing (especially in the aircraft industry) to the repair of various facilities. The Germans also had to produce enormous quantities of concrete to construct flak towers, shelters, and other structures necessitated by the bombing. The V-2 program, the most expensive weapons program the Germans developed during the war, was accelerated in response to the bombing as well. Fighter aircraft, as well as flak and anti-aircraft ammunition, became top priorities (the production of bombers virtually ceased by 1943). Finally, the Nazi regime had to redistribute existing forces (aircraft and flak) from the Eastern and the Mediterranean fronts to Germany. That meant that German ground forces increasingly had to operate without any air cover whatsoever. All of these changes availed the Germans nothing. The Luftwaffe entered a death spiral. Allied fighters escorting bombers over Germany shot down large numbers of enemy fighters. The pressure to produce new pilots (along with the decreasing supply of high-octane fuel) meant that the Luftwaffe spent less time on training than ever before. Badly prepared pilots flying poorly manufactured aircraft were not only shot down in ever larger numbers but also experienced huge non-operational losses. Meanwhile, the tactical and operational mobility of the German army was reduced (due to lack of fuel and the absence of air cover), and Germany suffered huge losses of armored fighting vehicles to Allied aircraft. O’Brien calculates that in 1943, the Germans lost a greater proportion of their military equipment in the air war over Germany than on the Eastern Front (314). Of course, in 1944, matters only grew worse for the Germans due to Allied strategic, operational, and tactical air superiority. Strategic bombing really began to undermine the German economy in the second half of the year. At the same time, the Germans lost more equipment during the Normandy campaign (at the fighting at the Falaise pocket) than they did during Operation Bagration in Russia (which was roughly concurrent), largely because Anglo-American bombers and fighters ruled the skies over France. O’Brien, then, produces much evidence to support the view that the Anglo-American strategic bombing campaign was truly the equivalent of a second front and then some.
The story is somewhat similar when O’Brien describes the US Navy’s offensive through the central Pacific toward the Mariana islands and the demise of Japanese fighting power. O’Brien rates Japanese industrial might rather highly; according to his figures, Japan produced about as much weaponry as the Soviet Union did in 1942 and 1943 (fewer tanks but many more ships). King might have lied to get the United States to devote more production to the Pacific theater, but it is clear that Japan was a very significant threat that made it very difficult for the Americans to hew to a “Germany first” strategy. Indeed, the United States eventually committed enormous amounts of air and sea power to the Pacific. The United States did manage, however, to deal a number of heavy blows to the Japanese even before American industry hit its stride and covered the sea with ships and the sky with planes. The Battle of Midway was a great blow to the Japanese because they lost four aircraft carriers. O’Brien, argues, though, that the fight at Guadalcanal did more to undermine Japanese power because of the heavy losses inflicted on the navy’s air arm. This grinding, attritional battle led to the combat deaths of many experienced pilots who were compelled to operate from distant bases that were themselves at the end of a very long logistical tether. Non-operational deaths were also extremely high. Although the Japanese proved extremely good at replacing aircraft (and then some) up until the second half of 1944, the loss of pilots proved catastrophic. The pressure to produce pilots as well as shortages of high octane fuel (due to the success of American submarines in sinking Japanese tankers who brought oil from the Dutch East Indies) led to reduced training and poor pilot performance. American superiority in the air supported what became a huge superiority at sea. O’Brien points out that the American naval assets devoted to the capture of the Marianas (which he sees as the decisive victory of the Pacific theater) were absolutely huge. Spruance’s 5th Fleet included 7 aircraft carriers, 8 light aircraft carriers, 7 battleships, 8 cruisers, 12 light cruisers, and 67 destroyers—ships worth a total of $2,500,000,000 in 1944 dollars (the equivalent of America’s spending on ground forces for all of 1942). The 15 aircraft carriers were armed with almost a thousand planes. A total of 46 tankers supported the fleet, carrying 4,500,000 barrels of oil, 8,000,000 gallons of aviation fuel, and 275,000 barrels of diesel. On the American side, the Pacific war had become capital-intensive, and the number of troops employed was actually quite small (although casualties were very high among the soldiers or Marines who saw combat). O’Brien argues that once the Marianas were captured, “the war was over strategically” (422). China, the Philippines, and just about any other island in the Pacific became irrelevant. The Americans could use aircraft based on the Marianas to bomb Japan as well as to interdict trade between Japan and its imperial possessions. Japan entered a terminal decline as its imports were sunk and factories were destroyed.
The implications of O’Brien’s arguments for the historiography of World War II are great. First, he elevates the significance of naval and especially air power over armies. Second, as his opening line suggests, he stresses attrition on the air-sea “super-battlefield” at the expense of traditional land battles. Third, he emphasizes the contributions of Britain and the United States to Axis defeat and, by implication, downgrades the Soviet Union’s efforts. Fourth, he underscores the degree to which the Allies won because they destroyed Axis mobility at the strategic, operational, and tactical levels. O’Brien suggests that two very different types of forces waged World War II. On the one hand, armies required a great deal of manpower but proved relatively cheap to put in the field. On the other, navies and air forces proved far more capital-intensive and technologically sophisticated in relation to the amount of manpower employed. The former looked somewhat to the past while the latter pointed to the future.
Elements of O’Brien’s argument may seem familiar, but they are buttressed with batteries of statistics that are presented in such a way as to make the reader look at matters in a new light (e.g. the development and production of the V-2 “cost Germany in relative terms as much as the Manhattan Project cost the United States” ). Since so much rides on statistics in this book, the question becomes, of course, are these statistics correct? This reviewer is not qualified to dispute O’Brien’s numbers, but it is worth pointing out that elements of the author’s arguments do rest on calculations and speculations of different sorts that other historians expert in the field might dispute. Other scholars are sure to take issue with the absence of the Soviet Union from most of this book. While O’Brien’s purpose consists of explaining the contribution of Anglo-American air and sea power to Allied victory, the title of his work suggests that this power was preponderant in defeating the Germans. Without investigating the Soviet Union to the same extent as the Western Allies, it is hard for the reader to know for sure. Finally, the stress on material factors (i.e. the production and destruction of munitions) tends to provide a lopsided view of the war. While O’Brien’s account does analyze strategy, it does not consider the significance of operations and tactics to the outcome of the war. For example, had the Japanese concentrated their carrier forces in the first half of 1942 instead of dispersing them in a series of fruitless raids and operations, the Americans very well could have been the ones to lose all of their carriers at Midway—and that would certainly have exerted a huge influence on the course of the war.
These quibbles aside, O’Brien’s work is an important reconsideration of the war if for no other reason that it reassesses the relative contributions of the Big Three to the defeat of Nazi Germany and Imperial Japan.