Book Review: 'How the War Was Won'

Phillips O'Brien has produced a history of the Second World War that is absolutely essential reading.

So before diving into my review of the book, I want to make clear that this book is excellent. A deeply researched and readable effort, it seeks to put into better balance the contributions of the various Allies to the war. In doing so, it serves as a corrective to the conventional wisdom, which centers the defeat of Germany on the vast struggle with the Soviet Union on the Eastern Front. Using voluminous reviews of the relative expenditures of the various powers across domains, O’Brien argues forcefully that the US and UK’s contributions to victory were just as, if not more important than, the heavy losses derived from the fighting on the Eastern Front. It’s an interesting and provocative read.

The reason I’m putting this disclaimer up front is that the conclusions are so compelling that they made me extremely curious about some of the methodologies involved and much of this piece will involve presenting O’Brien’s research and then thinking through how design choices might have influenced the data. I’m doing this not because I disagree with the broad contours of his argument – I’ve always felt that the conclusion that the vast destruction visited on Germany’s industrial by USAAF and Bomber Command somehow had minimal impact on the conflict was hard to sustain, but I’ve never seen the various contributions so carefully quantified. In order to do this, O’Brien leverages extensive research drawn from the United States Strategic Bombing Survey (USSBS) after the war and then uses that to show just how crucial the Air/Sea aspects of World War II are to overall victory.

To some extent, O’Brien’s perspective is almost Marxist – I don’t mean that as an insult, but to try to frame how he views the various contributions and losses suffered by the various power. It’s compelling, but it leads to questions about how one adequately captures the value of more intangible parts of war. That being said, the numbers are just incredibly compelling and worth recreating here. First, here are the USSBS estimates for German weapon production from 1942-1944:

The combined Air-Sea estimate is that roughly half of German weapons production was going toward Air-Sea activity. He creates a similar chart for ammunition, albeit at a slightly lower Air-Sea ratio.

Assuming these numbers to be accurate, it strongly suggests that much of the decisive work of the war was the destruction of German Air and Sea capabilities. O’Brien then marshals considerable evidence that the vast majority of that work was done by the US and the UK, in particular looking at equipment losses prior to combat as a key indicator of the efficacy of the air campaigns. He does not offer an unqualified defense of Bomber Command and the USAAF’s decision-making, but he does argue that they were, in the end, effective at destroying vast amounts of Germany’s war-making capabilities and has the numbers to back them up.

This then is where I get curious about the methodology of the USSBS. It’s easy to quantify production values based on expenditure by a given country – I do that pretty regularly in my day job. Budget documents give you a clear indication of the cost of everything to a government, from people to paper to Panzer tanks. I don’t know of the USSBS’s methodology, but I’d expect that that’s what they used, and the various interview vignettes O’Brien cites from German officials seem to support that.

However, I think the risk in using budget values in this specific context is that they are good at capturing costs, but not necessarily the best assessment of value. This is, in particular, an issue around capturing an important budget item not seen in these numbers - personnel. Personnel costs are a significant amount of any military’s budget but frequently the actual value of particular cohorts of soldiers, sailors, and airmen & women is not accurately reflected in those numbers. Military Personnel costs in the US budget currently account for just over 20% of defense spending whereas Procurement and RDTE spending account for roughly 34%. I have no idea how those numbers may have looked in the Second World War when the main combatants had over 5% of the population under arms. It seems difficult to make economic determinations without accounting for these sorts of expenses.

There’s also the issue that not all service members are valued equally. In 1941, the airmen of Kido Butai were veteran airmen who had years of experience flying and had graduated from a painfully long, multi-year training plan. The airmen flying in 1944 for the Imperial Japanese Navy heading into the Marianas Turkey Shoot had, for the most part, been sped through a training program that was a fraction of the time that it had been in the 1930s. I’d imagine similar, though likely not quite as extreme, variations existed in tankers in the Wehrmacht over a similar time period.

All of this is a long way of saying that, given the information provided, O’Briens’ thesis is really compelling and well-supported. However, I’d expect there’s more to be gleaned from expanding the aperture of costs and I wonder if the balance might shift to something a bit more equitable. I still think his work is an extremely useful corrective to the existing narrative but perhaps the air and sea campaigns, particularly in Europe, were not as decisive as portrayed here.

(I made some minor edits to this piece when I realized that I had not linked to the actual book for purchase at any point and added a hyperlink.)