Battle of The Atlantic - Assessment

Assessment

It is maintained by some historians the U-boat Arm came close to winning the Battle of the Atlantic, the Allies were almost defeated, and Britain was brought to the brink of starvation. Alan Levin states this is “a misperception”, and that “it is doubtful they ever came close” to achieving this, while a sober assessment confirms his view.

First, the Battle of the Atlantic was not a contest for naval supremacy, but a sustained attack on Allied commerce, which (Mahan tells us) cannot by itself win command of the sea. Germany in fact made little attempt to contend for this, using its surface force primarily as a fleet in being or as commerce raiders.

Second, the focus on U-boat successes, the “aces” and their scores, the convoys attacked, and the ships sunk, serves to camouflage the Kriegsmarine's manifold failures. In particular, this was because most of the ships sunk by U-boat were not in convoys, but sailing alone, or having become separated from convoys.

At no time during the campaign were supply lines to Britain interrupted; even during the Bismarck crisis, convoys sailed as usual (although with heavier escorts). In all during the Atlantic Campaign, only 10% of transatlantic convoys that sailed were attacked, and of those attacked only 10% on average of the ships were lost. Overall, more than 99% of all ships sailing to and from the British Isles during WWII did so safely.

Despite Axis efforts they were unable to prevent the build-up of invasion forces for the liberation of Europe. In November 1942 at the height of the Atlantic campaign the US Navy escorted the Operation Torch invasion fleet 3,000 mi (4,800 km) across the Atlantic without hindrance, or even being detected. (This may be the ultimate example of the Allied practise of evasive routing.) In 1943 and 1944, the Allies transported some 3 million American and Allied servicemen across the Atlantic without significant loss. In 1945 the USN was able to wipe out in mid-Atlantic a wolf-pack suspected of carrying V-weapons with little real difficulty.

Third, and unlike the Allies, the Germans were never able to mount a comprehensive blockade of Britain. Nor were they able to focus their effort by targeting the most valuable cargoes, the eastbound traffic carrying war materiel. Instead they were reduced to the slow attrition of a tonnage war. To win this, the U-boat arm had to sink 300,000 GRT per month in order to overwhelm Britain’s shipbuilding capacity and reduce her merchant marine strength.

In only four out of the first 27 months of the war did Germany achieve this target, while after December 1941, when Britain was joined by the U.S. merchant marine and ship yards the target effectively doubled. As a result the Axis needed to sink 700,000 grt per month; as the massive expansion of the U.S. shipbuilding industry took effect this target increased still further. The 700,000 ton target was only achieved in only one month (November 1942), while after May 1943, average sinkings dropped to less than one tenth of that figure.

By the end of the war, although the U-boat arm had sunk 6000 ships totalling 21 million grt, the Allies had built over 38 million tons of new shipping.

The reason for this misperception may be found in the post-war writings by both German and British authors. Blair attributes the distortion to “propagandists” who "glorified and exaggerated the successes of German submariners", while he believes Allied writers “had their own reasons for exaggerating the peril”.

Dan van der Vat suggests, unlike the U.S., or Canada and Britain's other dominions, which were protected by oceanic distances, Britain was at the other end of the transatlantic supply route; for Britain it was a lifeline. It is this which led to Churchill’s concerns. Coupled with a series of major convoy battles in the space of a month, it undermined confidence in convoy system in March 1943, to the point Britain considered abandoning it, not realizing the U-boat had already effectively been defeated. These were “over-pessimistic threat assessments”, Blair concludes: “At no time did the German U-boat force ever come close to winning the Battle of the Atlantic or bringing on the collapse of Great Britain”