For all those discussing the U-boat threat in the Battle of the Atlantic: This _is_ a perfect example of what I think Wretchard was talking about: to a great degree history is an illusion we carefully build for ourselves. There is only one valid source for history: the facts as recorded by the men and women who were there at the time. I never trust any hearsay source — and anyone who hasn’t read the primary sources him/herself is just repeating hearsay.

To that end, I’d like to point you to two sources which I do consider trustworthy. One is a now-rather-old book, probably hard to find, called VERY SPECIAL INTELLIGENCE by Patrick Beesly. Beesly is as primary a source as you can get: he worked in the British Admiralty’s U-boat Tracking Room during the war, and VERY SPECIAL INTELLIGENCE is basically his personal memoir of the Operational Intelligence Centre and its work. The second is BLACK MAY by Michael Gannon, a study of the critical months of the battle of the Atlantic, including but not limited to May 1943, when the Allied navies wiped out a third of the operational U-boat fleet in thirty days. Gannon went back to the primary sources for his research, including freshly-declassified material that earlier historians never had access to.

Both authors agree that the conventional picture of ravening U-boat hordes nearly cutting the North Atlantic convoy lanes is wrong. There was never any real chance of it happening. The peak of the U-boats’ success was March 1943; by that time, though , the trends being tracked in the Tracking Room showed clearly that the U-boats couldn’t win in the long term. Ships were being built faster than U-boats could sink them, escorts were gaining steadily in ASW expertise, and U-boats — and more importantly, experienced U-boat crews — were being lost faster than Doenitz could replace them. Black May was not a miracle; it was simply inevitable.