How Certain was Allied Victory in WWII?

By Aaron Bauer

April 16, 2018

Richard Overy's Why The Allies Won is the most persuasive work I've read on this subject. He argues that Allied victory was in no way preordained and that an analysis relying entirely on aggregate material advantage risks dramatic oversimplification. To me one of the most interesting questions he raises is why were the Axis powers unable to capitalize on the material advantage they held up until 1942? Both Germany and Japan began with distinct advantages and proceeded to conquer large areas rich in resources in the opening years of the war. How is it that Allied fortunes changed so dramatically between 1942 and 1944? In a conflict of such scale and complexity, Overy says, "the chances of a single battle or decision seriously explaining its outcome are remote."

Overy divides his analysis into two approaches: (1) the four main zones of conflict where the Allies were able to gain the upper hand (the war at sea, the eastern front, the war in the air, and the reconquest of Europe) and (2) the preconditions and causes of that military success (the balance of resources, combat effectiveness, leadership and strategic judgement, mobilization of the home front, and the moral contrasts between the two alliances). I'll try and summarize some of the most compelling parts of this analysis below, though I will necessarily be omitting much of the wonderful detail of Overy's book. I strongly recommend giving it a read if this subject interests you.

The Submarine Menace

As a island nation with a vast overseas empire, shipping was essential to Britain’s ability to continue the fight against Nazi Germany. The Royal Navy was faced with the herculean task of keeping global sea trade flowing. Control of the seas was vital to the United States as well, since supplies and equipment had to flow freely from American shores if the country was ever to fulfill Franklin Roosevelt’s exhortation to become the “arsenal of democracy.” Hence, Germany’s submarine fleet posed an existential threat to the Allied war effort.

At the outbreak of war, Britain was largely unprepared for the submarine threat. Despite being few in number in the war’s early years, the German U-boats strangled Britain’s imports from 68 million tons in 1938 down to 26 million tons in 1941. This rampant success led Germany to pour resources into submarine production, expanding a fleet of a couple dozen to hundreds of vessels. After American entry into the war following Pearl Harbor, submarines targeted the vulnerable eastern seaboard, sinking 1.2 millions tons in the first four months of 1942 alone. This was a rate of loss beyond what Allied shipyards could replace, and by January 1943 the British had only two months’ supply of oil.

The Allied solution was combination of better planning, better intelligence, and, most importantly, technological improvements that allowed the Allies to take the fight to the submarines. The British and Americans set up a coordinated effort to track the positions of German submarines and route convoys around them. The Royal Air Force developed improved radar that, thanks to using shorter wavelengths, was able to avoid interference from waves and spot surfaced submarines at long distances. Finally, the US developed very-long-range aircraft which, when equipped with searchlights and the new British radar, could protect convoys day and night from the air anywhere in the Atlantic. Even as the size of the German submarine fleet increased, the amount damage inflicted on shipping was held in check and then put into decline. Submarine losses also began to mount to point where by mid-1943, U-boats were being sunk faster than cargo ships. The commander of the German submarine fleet Karl Dönitz recognized defeat and ordered all submarines to retreat from the Atlantic in May 1943, removing the greatest threat to Allied shipping.

Russian Resilience

In June 1941, the largest invasion force in human history invaded the Soviet Union. Code named Operation Barbarossa by the invading Germans, the offensive shattered the Red Army and drove rapidly for Moscow. Joseph Stalin’s army purges of the 1930s and his insistence that Hitler wouldn’t attack left the Soviet military unprepared to resist German military might. Crucial areas of agricultural and industrial production were lost as the Red Army retreated, depriving the Soviets of half of their gain supplies, 40 percent of their electricity generating capacity, and three-quarters of their iron ore, coal, and steel. The situation was so dire that Stalin even contemplated surrender in late 1941.

How then did the Soviet Union claw its way back not just to withstand the might of a Nazi war machine that had rolled over much of Europe in just a matter of months, but to deal Hitler's forces crushing defeats from which they never recovered? One key element of the story is the almost unbelievable resurgence of Soviet war production, which managed to turn out more weapons in 1942 than 1941. This comeback was made possible by the physical relocation of entire factories and workforces east across the Ural Mountains, out of reach of German forces. As the Germans advanced, machines, supplies, factory workers, engineers, and plant managers were all frantically loaded onto trains headed east. Massive new factories sprung up along with millions of relocated workers to get them running. Soviet planners, used to overseeing the nation’s economy with near complete authority, directed all possible materials and labor to increase war production. The brutal conditions and single-minded purpose paid dividends, as from 1942 on Soviet factories turned out more weapons and equipment than their German counterparts despite having considerably less in the way of raw materials and skilled workers.

The USSR was by far the most mobilized nation in the war, not just in military production, but in manpower as well. Before the invasion began, German military planners correctly estimated that the Soviets had 150 divisions. Where they went wrong is that they believed the Soviets could add at most 50 more to this total. In fact, the Red Army was able to form more than 200 new divisions. Imagine the alarm among the German High Command when they continued to face significant Soviet forces after having destroyed as many Soviet divisions as they believed existed.

This tenacity led to the two key turning points on the eastern front: Stalingrad and Kursk. Improvements in Soviet planning, military organization, and the quality of equipment put the Red Army on equal footing with Germany’s Wehrmacht. The fierce determination and shared sacrifice of the Soviet people, both soldiers and civilians, made possible the enormous losses inflicted on the Germans throughout the terrible siege of Stalingrad and the decisive victory when the Soviets counterattacked at the Battle of Kursk.


Bombing during the second world war has been a source of intense debate in both moral and strategic terms. In both Britain and the United States, the focus on bombing was driven in part by fantastic expectations of its ability to prove decisive. It was believed that so-called strategic bombing, the use of bombing to destroy enemy industry and to terrify the enemy population, could remove an opponent’s capacity to make war altogether. In practice, bombing was unable to deliver on these grandiose claims. Bombing was extremely inaccurate, especially early in the war. A study of British efforts in 1941 concluded that even in the best of conditions, only a third of bombers got within five miles of their intended target. Bombing also completely failed to damage the morale of either side. A poll asking Londers what depressed them most about the winter in early 1941, a time during which the German air force was pounding the British capital, found that the weather came out ahead of bombing. Nor did strategic bombing cripple economic output, as German military production tripled 1941–44 despite the massive bombing of German cities.

Nevertheless, bombing had significant effects and played an important role in Allied victory. After the conquest of Poland and France, Nazi Germany was poised to become an economic super-power with nearly all of continental Europe at its disposal. Bombing served to disrupt these economic ambitions. Time and resources that could have been put toward increasing production were instead diverted to repairing damage to infrastructure and factories. Furthermore, intensified bombing from 1943 onward forced German industry to disperse to more spread out and secure locations just as efforts at adopting mass production techniques were getting underway. Finally, the bombing campaign kept significant German forces, especially aircraft and pilots, on the homefront and away from the fight against the USSR. The Nazi War Production Ministry estimated that in 1944, bombing reduced the production of tanks by 35 percent, aircraft by 31 percent, and trucks by 42 percent. While bombing didn’t wipe out Axis production, it dealt a severe blow that certainly ranks it among the key elements of Allied victory. Whether this impact merits the immense resources devoted to the bombing campaign or justifies the indiscriminate killing of civilians is a far more complicated question and one that continues to deserve serious attention in our modern era of drone and missile strikes.

Economic Advantage

The United States would indeed become the arsenal of democracy (not to mention Stalin’s Communist dictatorship), but at the start of 1941 this was far from obvious. Though America produced more steel, aluminum, oil, and cars than all the other major combatants combined, years of disarmament and isolation since the end of World War I left it with little in the way of military industry. President Franklin Roosevelt and his administration knew that they couldn’t seize control of the nation’s industry or decree that factories switch from cars to tanks. Instead, American authorities had to rely on the initiative and profit motive of the nation’s leading industrialists.

An illustrative scene occured a month after the attack on Pearl Harbor: the Chairman of the Office of Production Management William Knudsen got a bunch of leading businessmen together in a room and went through a long list of military equipment, asking for volunteers to produce each one. Corporations were eager to volunteer for lucrative military contracts and soon American manufacturing was applying its talent for mass production to military needs. The scale of this shift was enormous: in 1941, 3.5 million passenger cars were produced in the US; during the following years of war, this dropped to just 139 cars. General Motors contributed a full 10 percent of all American war production, while the Ford Motor Company produced more army equipment than Italy. Mass production was not limited to trucks and tanks—American engineers found new ways to accelerate the manufacture of ships and planes. US shipyards turned out 16 major naval vessels for every one constructed in a Japanese shipyard, while Ford assembled “the most enormous room in the history of man” that, at its peak, turned out one bomber every 63 minutes.

On the Axis side, Germany didn’t lack for factories, engineers, or materials, so why did it fall so far short of what its resources could have made possible? After expanding rapidly in the 1930s, German military production stagnated in the early years of the war. Though many factors contributed including incomplete preparations when conflict began in 1939 and dysfunctional Nazi Party administration, the bulk of the blame falls on the German military itself. Intent on overseeing weapons production to the last detail, military officials made endless design changes and set production schedules without consulting industrialists or engineers. The result was a mess of different projects (at one point Germany had 425 different aircraft models in production compared to the Soviet’s five standardized types) few of which were produced in any significant quantity. The German military mistrusted “American” production methods, preferring sophisticated, custom-built weaponry. German equipment was indeed of exceptional quality, but as the war went on shortages grew. It took until 1943 and 1944 for real reforms to be made and mass production techniques to be put into place. By this time, Germany was far behind the US and USSR and the bombing campaign blunted any significant gains.

Leadership and Organization

Fighting a world war is an extremely complicated business. No single person is capable of effectively managing the efforts of an entire nation across vast battlefronts. Though Winston Churchill, Roosevelt, and Stalin were all the commanders-in-chief of their respective country’s armed forces, they each quickly realized the absolute necessity of delegation. Around each of these leaders assembled a core of military and civilian managers that oversaw the actual running of the war. Even under Stalin’s paranoid and brutal personal dictatorship, a stable and meritocratic staff emerged that effectively organized the fight against the German invasion. The committee-based approach taken by each Allied power was crucial for both organizing a unified war effort and preventing the flaws of a single leader from metastasizing and sapping the capability of an entire nation.

Hitler, like the Allied leaders, was the Supreme Commander of his nation’s military. Unlike them, he tooks this role to a messianic extreme and, with no regard for his limitations, refused to delegate any meaningful responsibility. Whereas Churchill, Roosevelt, and Stalin all took less of a direct role in military affairs as the war progressed, Hitler placed more and more under his direct control. Hitler’s hubris and desire for control prevented the establishment of both a professional staff and any kind of unified command for the different service branches and other areas of the war effort. Instead, all the various moving parts of the German war effort competed for Hitler’s attention, with predictable chaos as the result.

Germany was at the mercy of Hitler’s erratic judgement tactically as well as strategically. In reoccupying the Rhineland, annexing Austria and the Sudetenland, invading Poland in 1939, France in 1940, and the USSR in 1941, the Führer took risks few other leaders would have faced. His power and personal dominance cowed the German generals, who failed to make their objections known. Early success cemented Hitler’s belief in his innate military genius. The instability of one-man rule asserted itself in 1942 when Hitler diverted a large portion of German forces on the Russian front south to capture the Caucasus oil fields rather than concentrating everything on taking Moscow. As the eastern situation worsened, Hitler fired top generals and took personal control of operations. He surrounding himself with military lackeys who possessed sufficient “National Socialist spirit.” Hitler’s will and unshakable faith in his personal destiny played a key role in both the rise and fall of the Third Reich.