Engineers of Victory

by Paul Kennedy

  Two other inestimably important factors at play in battles of such strain, anxiety, and loss as the convoy shoot-outs were leadership and morale. As we shall see below, the element of morale did turn significantly to one side’s favor later in the Atlantic campaign, after mid-1943, but on the whole the bodies of combatants were fairly evenly matched in this dimension. Doenitz and Horton were worthy opponents, and the latter received a great reinforcement when Air Marshal Sir John Slessor took over as C in C of RAF Coastal Command in February 1943: Slessor was dedicated to defeating the U-boats and a firm advocate of air-sea cooperation even if it involved frequent fights with Harris at Bomber Command over the allocation of planes. Doenitz had an extremely competent deputy, Rear Admiral Godt, for the day-to-day management of the U-boats, though very few middle-ranking staff. An enormous responsibility was thus placed upon the U-boat commanders themselves, many of whom became legends, not unlike the First World War fighter aces, with an instinct for both killing and surviving despite the very high loss rate—until the strain became too great. As we shall see, there was little evidence that Allied morale, whether of captains or crews, Royal Navy personnel or merchant sailors, ever sagged even when losses and general conditions were at their worst. Moreover, the Western Allies simply possessed far more trained officers of the captain and commander rank, not to mention naval reserve officers who could be thrown into any breach.

  The remaining factor has to be that of relative force strengths and endurance. It was not just the measure of crews’ physical and mental stamina during a fourteen-day convoy struggle; it was also a matter of sustaining each side’s campaign through reinforcement, sending fresh numbers to replace those lost, and steadily building up the fighting punch of one’s service. This was total, industrialized war, measured most clearly by the flows of new U-boats vis-à-vis Allied warships and aircraft, of merchant vessels, and of fresh crews. Here again, one might have assumed that by early 1943 the odds were tilting in Doenitz’s favor; certainly the steady buildup in U-boat numbers pointed to that conclusion. Moreover, while German shipbuilding production could concentrate ever more narrowly on submarines and lighter attack craft (E-boats), British yards were being stretched to produce light fleet carriers for future Far East operations, newer classes of cruisers and destroyers, landing gear, and the Royal Navy’s own submarines. Had it not been for the stupendous gearing up of American war industries as 1942 unfolded into 1943, this could have been a very one-sided production battle. In any event, at the time of Casablanca no one on the Allied side was very cheery about how the naval odds looked in the Atlantic.

  The Battle at Sea, and the U-boats’ Triumph

  As Hitler’s attack upon Poland in September 1939 led to the Anglo-French declarations of war, the strategic situation in the Atlantic basin and across western Europe was eerily similar to that of a quarter century earlier, when the Entente Cordiale and its empires had gone to war in response to Germany’s invasion of Belgium. A small British Expeditionary Force (BEF) once again crossed the Channel to stand with the French armies. The other countries of Europe remained neutral, as did the United States, due to congressional fiat. Most of the British dominions (that is, Australia, Canada, Newfoundland, New Zealand, and South Africa, but not, unhappily, de Valera’s Eire) joined the struggle, as did the dependent parts of the Anglo-French empires. The Royal Navy assembled its surface fleets at Scapa Flow and Dover to close the two egresses from the North Sea, except of course to a small number of German commerce raiders already in the wider oceans. The broad impression that history was indeed repeating itself was fully captured, symbolically and physically, by Churchill’s return to the revered cabinet position of First Lord of the Admiralty, the position he had occupied in 1914. “Winston is back!” went out the message to the fleet.

  The strategic position at sea could not have been worse for the German navy, headed by Raeder. His service did indeed have plans (the famous Z Plan) for a massive transoceanic battle fleet, with giant battleships, aircraft carriers, and all, but even Nazi Germany’s formidable production capacities could not produce such a force—or even a quarter of it—by 1939. Another four or five years at least were needed, and Raeder had believed the Fuehrer would keep out of a major war for that long. He, like a lot of Wehrmacht generals, was badly mistaken. The German navy thus went to war with a force completely inadequate to match the Allied navies, with a service starved of the resources allocated to the German army and the Luftwaffe. Even its U-boat arm was weak, small in numbers, short in range, and forced to go all the way around northern Scotland to reach the broad Atlantic. The overall odds looked hopeless.

  Those odds changed, in the most dramatic ways possible, during May and June 1940. The collapse of France and Belgium, and the escape of the battered BEF through Dunkirk, meant there was no longer a Western Front. Worse still, the Luftwaffe could now operate against England out of forward bases in Pas-de-Calais, while the German navy could steam in and out of Brest and the Gironde. To compound these disasters, there was the staggeringly fast Nazi takeover of the Netherlands, Denmark, and Norway, with all the consequent strategic and geopolitical implications. Now all the waters beyond the Channel and North Sea were open to German surface ships and submarines. The odds tilted further when Mussolini, cagily neutral in September 1939, opportunistically declared war on the British Empire and a falling France on June 10, 1940. An entire new navy, including one of the world’s largest fleets of submarines, entered the war on Berlin’s side, just as most French warships were abandoning hostilities and anchoring in Toulon and the North African ports.

  The result was that—after the Battle of Britain and the survival of the island nation itself in 1940—the Battle of the Atlantic became the center of the western struggle. Once the immediate German invasion threat diminished, the various British countermoves—such as the maritime relief of Gibraltar, Malta, and Cairo, the preservation of the Cape routes to the East, the military buildups (including dominion and empire forces) in Egypt, Iraq, and India, and the development of the early strategic bombing offensive against the Third Reich—were, while critically important, impossible to sustain unless a constant flow of foodstuffs, fuel, and munitions reached the home islands from across the seas and new British divisions and weaponry were carried from the home islands to Africa and India. That simple strategic fact did not change when Germany attacked the USSR in June 1941, or when Japan’s attack on Pearl Harbor in December 1941 and Hitler’s reckless declaration of war against the United States turned a European war into a global conflict. Indeed, the importance of winning the Battle of the Atlantic was only reinforced by the Anglo-American decision to build up a force of millions of men in the United Kingdom for the future invasion of western Europe.

  Thus the struggle to defend the sea-lanes simply to preserve the British Isles now became a gigantic fight by the Allied navies as the first step in ensuring Germany and Italy’s unconditional surrender. Fortunately for the British, the German surface threat could never reach full fruition (just as Raeder had warned). The sinking of the giant battleship Bismarck in May 1941 eliminated the greatest single danger, and the “Channel Dash” of the other German heavy ships from Brest back to Germany in February 1942, though highly embarrassing to the Royal Navy’s pride, put those warships once again into constricted waters, to be continually screened by the Home Fleet at Scapa and bombed repeatedly by the Royal Air Force. Futile and rather halfhearted sallies against Arctic convoys offered no challenge to the Allies’ command of the sea. Only the submarines could do that.

  And that they did very well. As the number of U-boats available to Doenitz rose steadily during 1942, their crews also grew in experience, their detection equipment became more reliable, their range was increased by the introduction of “milk cow” refueling subs, and they were masterfully coordinated by Doenitz. America’s entry into the conflict gave them fabulous opportunities against a new enemy and his merchant fleet, almost completely unprepared for this type of warfare, all th
e way along the still floodlit eastern coast. Longer-range submarines were sent farther afield to pick off rich targets near Sierra Leone, in the eastern Caribbean, off Buenos Aires, and off the Cape. But Doenitz never stopped hammering away on the crucial North Atlantic routes.

  Total Allied shipping losses had jumped from about 750,000 deadweight tons in 1939 to an awful 3.9 million tons in the chaotic year of 1940, increased in 1941 to 4.3 million tons, and then soared again in 1942, as we have seen, to a colossal 7.8 million tons. Of course, there were heavy losses in other regions—off Dunkirk, in the South Atlantic, in the Mediterranean, and by 1941–42 in the Far East—but the heaviest losses (for example, 5.4 million tons of the 1942 grand total) occurred in the North Atlantic. By comparison, Doenitz’s U-boat losses were moderate in those years: around twelve in 1939 and around thirty-five in 1941, increasing to eighty-seven in 1942. These U-boat losses were completely sustainable; the merchant ship losses—and equally the losses of their experienced crews—were much less so.6

  It is therefore not surprising that the shipping losses of March 1943 scared Churchill and the Admiralty. If Doenitz’s wolf packs could inflict that much damage during dark and stormy conditions—the main attacks ceased only after March 20, when already rough waters were joined by what was essentially a massive Atlantic hurricane—the planners worried how their Allied convoys could survive in lighter and calmer times, with the moon shining across the waters. Would the loss rate double again by May and June? And were the submarines becoming harder and harder to trace and to sink? The jubilant U-boat crews and their determined admiral must have hoped so.

  And yet the one-sided results of the March battles were never repeated again. In fact, they turned out to be the high point of the submarine offensive against Allied shipping, a momentary peak that then fell away so precipitously that each side was stunned by the transformation. It is hard to think of any other change in the fortunes of war that was both so swift and so decisive in its longer-term implications.7

  Precisely because it was so, it is important to take a closer look at the epic convoy battles of March to May 1943, when the balance of advantage swung so decisively from U-boat triumph to U-boat disaster. Fortunately, the sources for this story are excellent, down to the hour-by-hour tracking of virtually every submarine’s movements and the turn of every convoy.8

  The month of March began badly for the Allies. While the American, British, and Canadian naval authorities were at their Atlantic Convoy Conference, hammering out decisions regarding zones of control, reinforcements, and the rest, a confident Doenitz was dispatching more and more submarines to join each of the four large wolf packs he had established in the central Atlantic, usually two in the center and one each on the northern and southern flanks. Moreover, at this stage in the intelligence/decryption conflict the Germans very much possessed the upper hand; B-Dienst was providing its chief with extraordinarily complete descriptions of the time and course of the Allied convoys, sometimes even before they left harbor. By contrast, the code breakers at Bletchley Park and at the Admiralty were having difficulty reading German messages days after they were sent. In sum, the shepherds, though gallant, were more than normally disadvantaged, weaker than usual, groping in the dark. The wolf packs were ready to pounce.

  Thus their slaughter of Convoy SC 121, which sailed from New York to various British ports on March 5, 1943. Despite the weather being perfectly foul, some U-boats not picking up signals, and a late rush of a few Allied escort reinforcements, the odds were overwhelmingly in Doenitz’s favor. The great expert on these March convoy battles, Juergen Rohwer, provides us with a meticulous order of battle:

  The SC.121 … consisted originally of 59 ships and … was escorted by the Escort Group A 3 under Capt Heineman, USN, with the US coastguard cutter Spencer, the US destroyer Greer, the Canadian corvettes Rosthern and Trillium and the British corvette Dianthus. The Commander U-boats [i.e., Doenitz] deployed against this convoy the Westmark group comprising U 405, U 409, U 591, U230, U 228, U 566, U 616, U 448, U 526, U 634, U 527, U 659, U 523, U 709, U 359, U 332 and U 432. At the same time he ordered U 229, U 665, U 641, U 447, U 190, U 439, U 530, U 618 and U 642 … to form another patrol line, Ostmark, on the suspected convoy route.9

  So there were fifty-nine vulnerable and slow merchantmen, with initially only five escorts, against twenty-six U-boats, and with no air cover for the convoy until the third day of the fight—and what was air cover anyway if the submarines attacked chiefly at night? The result was an ordeal from March 7 until March 10, when Doenitz called off his boats. Thirteen merchant ships totaling 62,000 tons had been sunk, but not a single submarine had been lost. It was perhaps the most disproportionate, one-sided battle of the entire war—and was deeply satisfying to Hitler, to whom Doenitz regularly reported.

  There were, however, another couple of early March convoys across the Atlantic that also command attention. Convoy ON 170, for example, was ably directed away from all of these deadly mid-Atlantic battlefields and thus steamed across the northern waters without a loss and without (so far as we can tell) an encounter with a U-boat. Here was the case for shepherds and sheep simply taking the high Alpine passes and avoiding the wolf-strewn valleys below. Many an Allied convoy, in fact, survived the crossing unscathed, either because of clever routing or simply because Doenitz had directed all his boats to go after a different one.

  A more mixed story is that of Convoy HX 228, which fought its way across the Atlantic between March 7 and 14 in a craziness and confusion that might remind naval historians of Nelson’s entanglements with the French fleet at the Battle of the Nile (1798). At one stage in this battle the destroyer HMS Harvester, having rammed U 444, got its propeller shaft entangled in the latter’s rudder and was only released by the French frigate Aconit ramming and sinking the submarine. The Harvester was torpedoed the next day, but the Aconit promptly sank the submarine that had done so, U 432. At the end of it all, HX 228 lost only four merchantmen plus the destroyer, while the escorts—joined, limpingly, by the first escort carrier, USS Bogue, a harbinger of things to come—kept a good account of themselves throughout. The U-boat crews were composed of formidable and intrepid men, but the British, American, and Canadian sailors—a small number of old hands and a vast recruitment of new officers and crew to their navies and merchant marines—showed themselves on this occasion to be equally resourceful.

  However suggestive of a possible Allied recovery at sea, these hints were swept away by the achievements of the U-boats against convoys HX 229 and SC 122 between March 16 and 20. This was the most frightening moment, and not just for the fate of those two groups of merchantmen but for the overall convoy strategy as well.

  Unlike a classic land battle (between Greeks and Spartans, or Wellington and Napoleon), where each opponent was roughly similar in composition, the two sides’ forces in the Atlantic struggle were very different. Doenitz’s U-boats were, roughly, all the same; the captain and crew of an older Type VII submarine were no doubt envious of those in the faster, larger, and better-equipped Type IXs—unnecessarily, as it turned out—but all of them could reach out far into the Atlantic, fire their deadly torpedoes, and dive fast, away from counterattack.10 By contrast, the Allied convoys contained a motley assembly of ancient tramp steamers, ore carriers, oil tankers, mail and passenger ships, and refrigerated ships.b The cargoes they carried were equally heterogeneous—grain, linseed, meat, army supplies, aircraft fuel, sugar, bauxite (for aluminum), steel, tobacco, “African produce” (probably vegetable oil and hardwoods), and everything else needed to keep a nation of forty million people at war. British and American merchant ships were reinforced by boats flying the Panamanian, Norwegian, Greek, Polish, and Dutch flags. One of the unintended consequences of Hitler’s aggressions was that the island state’s limited fighting resources were boosted by considerable numbers of foreign merchant ships and crews, foreign fighter and bomber pilots, and foreign infantrymen—and Britain was happy to take them all.

 
; The story of convoys HX 229 and SC 122 confirmed that the Royal Navy faced one of the greatest logistical challenges in all of military history. There were thousands of Allied merchant vessels on the high seas at any given time—probably up to twenty convoys, plus hundreds of independently sailing boats. From Trinidad to New Jersey, and from Adelaide to the Cape, the lines stretched out, with most of this produce ultimately destined for the critical North Atlantic passageway. As the maritime war unfolded, the convoys would necessarily become larger and larger, which was no bad thing in itself. During the Casablanca discussions on the shipping crisis, P. M. S. Blackett, the Admiralty’s chief of operational research, had impressed listeners with an analysis showing that a convoy of sixty or even ninety ships was a more efficient way of getting goods across the Atlantic than a convoy of thirty; the number of escorts remained roughly the same, limited more by shipbuilding production and other duties (Operation Torch) than anything else, and the U-boats only had a limited number of days and hours in which to attack, and a limited number of torpedoes, too. That mathematical analysis reinforced the planners’ conviction that the convoy system was the best one to pursue, but it still left a practical problem: how on earth did one get such a large and heterogeneous bunch of merchant ships from one side of the ocean to the other, especially when the Allied warships were themselves such a mixed bag of destroyers, frigates, corvettes, cutters, trawlers, and others?