The winter of 1939-1940 was the coldest in forty years. In early January the Baltic Sea, the Kiel Canal, the Elbe River, and the Jade froze solid. The bitter cold and the thick ice drastically impeded U-boat construction, repairs, training, and movements. The Germans pressed every spare surface vessel into service to break ice, including the old battleship Schleswig-Holstein, and fitted the U-boats with wooden casings to protect the bow torpedo doors. But numerous U-boats incurred ice damage and some were locked fast to Baltic piers, unable to move.
To escape the ice, Dönitz was compelled to forward base the U-boats at the island of Helgoland, in the warmer, ice-free North Sea. German submariners passionately hated this bleak, desolate, windswept, bitterly cold outpost. All facilities for men and ships were primitive. It was difficult to get fuel oil and spare parts through the ice to the island. British submarines prowled the nearby ice-free areas designated for sea trials and training. RAF bombers made occasional raids.
In January 1940, five boats sailed from Helgoland for torpedo patrols in the Atlantic. These included the cranky and clumsy Type I, U-25, which had twice aborted in December; two new VIIBs, U-51 and U-55; and two Type IXs, the Veteran U-41 and a new one, U-44. These boats carried submarine torpedoes in which no one had the slightest confidence. Dönitz summarized the torpedo situation in his war diary:
The fact that its main weapon, the torpedo, has to a large extent, proved useless in operations has been the greatest difficulty with which the U-boat arm has had to contend since the beginning of the war and it has had a most serious effect on results. At least 25 percent of all shots fired have been torpedo failures. According to statistics covering all shots up to 6 January, 40.9 percent of unsuccessful shots were torpedo failures…. The commanding officers’ and crews’ confidence in the torpedo is very much shaken. Again and again the boats have tried in the face of strong enemy activity to fire their torpedoes under the best possible conditions and often when they have made a daring attack they have been rewarded with failures and even danger to themselves…. It is very bitter for commanding officers and the executive control to find that the U-boat arm cannot achieve the success expected of it, in spite of thorough peacetime training, because of torpedo failures. I will continue to do all I can to keep up the fighting spirits of the U-boats in the face of all the setbacks.
However, there was then reason for optimism. Raeder had sacked the hidebound chief of the Torpedo Directorate, Oskar Wehr, and appointed a new chief, Oskar Kummetz, and had named the scientist Dr. E. A. Cornelius “Torpedo Dictator.” Kummetz was a contemporary of Dönitz’s and an officer of “great energy.” The new men, Dönitz believed, were “unprejudiced” and both brought fresh, inquiring minds to bear on the technical problems. After merely a few days on the job, Kummetz had telephoned Dönitz to say that he and Cornelius had conducted new tests, which had proved beyond doubt that the torpedoes were defective in several ways. This was an impressive bureaucratic victory for Dönitz, but the task of correcting the defects remained.
Because of the cold, the ice, and other factors, crews of the two new VIIBs, U-51 and U-55, embarking on maiden war patrols, were not fully trained. Dönitz therefore directed both skippers to patrol in low-intensity ASW areas west of Ireland, to gain further experience before attacking enemy shipping. But neither skipper was keen on conducting a training patrol.
On the day he reached the Atlantic, Dietrich Knorr, age twenty-seven, commanding U-51, took the boat straight into action. He sank a 1,600-ton Swedish freighter, then went directly to the Western Approaches, where he sank a 1,500-ton Norwegian freighter, from which he rescued two survivors. But U-51 developed a problem in her bow torpedo tubes and Knorr was forced to abort and return to Germany.
The brand-new U-55, commanded by Werner Heidel, age thirty, who had done well in the duck U-7, also went directly into action. Rounding the British Isles, Heidel sank two small neutrals (a Dane and a Swede), then proceeded to the Western Approaches. On the tenth day of the patrol, January 29, Dönitz alerted Heidel to a convoy, which had been detected by B-dienst. Heidel responded by sinking the 5,000-ton British tanker Vaclite and a 5,000-ton Greek freighter.
One of the convoy escorts, the sloop Fowey, left the convoy and pursued U-55 in foggy seas. Fixing the boat on sonar, Fowey attacked with depth charges, driving Heidel to 328 feet. Fowey dropped five charges, three set for 500 feet by mistake, two for 350 feet. The two set at 350 feet exploded very close to U-55, causing severe flooding and panic. Heidel temporarily contained the damage and panic and slipped away, but Fowey continued to hunt aggressively through the fog and called for help. Two British destroyers, Whitshed and Ardent, and a French destroyer, Valmy, responded, as did a four-engine Sunderland flying boat of Coastal Command Squadron 228, piloted by Edward J. Brooks.
The four ships and the aircraft hunted the damaged U-55 relentlessly. Whitshed got sonar contact and attacked with depth charges. By that time the U-55 crew could no longer contain the flooding. Believing he might escape in the fog, Heidel gave orders to surface and man the deck gun. Fowey sighted U-55 making off in the fog and opened fire. Valmy and the Sunderland joined. The Sunderland dropped a bomb and, helpfully, a smoke float and then made a strafing run. Heidel returned the fire—until the breechblock of the gun jammed.
Gunless, unable to dive, Heidel was left no choice but to scuttle. The first watch officer and chief engineer volunteered to help Heidel open the vents. When the boat started under for the last time, there was no sign of Heidel. The survivors believed he chose to go down with the boat. The other forty-one men of the crew launched a rubber life raft, jumped into the icy water, and were picked up by Fowey and Whitshed.
The loss of U-55 was known immediately to Dönitz. Eager to give a lift to the Coastal Command aviators who had patrolled the seas endlessly for months with no confirmed success, the RAF publicly claimed credit for the kill on January 31. The surface forces grudgingly conceded that the Sunderland may have helped—but not all that much. However, a British assessment committee gave Coastal Command partial credit for the kill along with Fowey and Whitshed. Doubtless some fault for the loss lay in Dönitz’s decision to send U-55 against an escorted convoy before she was adequately trained.
The three large boats, U-25, U-41, and U-44, were directed to patrol off the Iberian Peninsula. Arrangements had been made for any or all of these boats to secretly refuel and replenish from a German ship, Thalia, which had been left in the Spanish port of Cadiz for that purpose.
The clumsy and cranky U-25 and the brand-new Type IX U-44 led the way. En route, both boats found good hunting in the Shetlands area. Viktor Schütze in U-25 sank three freighters (one Swede, one Norwegian, and one British) for 13,000 tons. While passing southbound through the Western Approaches, Ludwig Mathes, age thirty-one, commanding U-44, also sank three freighters (one Norwegian, one Greek, and one Dutch) for 14,000 tons.
After reaching the Iberian Peninsula, Mathes came across several convoys. Operating alone and shooting torpedoes that worked to perfection, in a period of ten days Mathes sank five more ships (two French, two Greek, and one Danish) for 15,500 tons. Distrustful of the proposed secret refueling in Cadiz, Mathes exercised a skipper’s option and returned to Germany, where he was showered with ecstatic praise. Overcrediting him by 8,000 tons and perhaps forgetting that Hartmann in U-37 had also sunk eight ships in one patrol (for greater tonnage), Dönitz declared the U-44 patrol to have been “perfectly executed” and the “most successful” to date against merchant shipping.
Passing southbound through the Western Approaches, Viktor Schütze in U-25 sank his fourth ship. Since the OKM was anxious to test the secret Cadiz base and U-44 had declined the opportunity, Dönitz directed Schütze to refuel from Thalia. Schütze sneaked U-25 into Cadiz on the night of January 30, took on food, oil, and other supplies, and returned immediately to sea. There Schütze promptly sank his fifth ship, a 6,800-ton British freighter.
At that time, ten German merchant ships in Vigo, Spain, were preparing to run through the British blockade to Germany. In order to provide them some protection, the OKM directed Dönitz to assign U-25 as an escort. Dönitz protested. Submarines were useless in an escort role. They could not keep up submerged; while traveling on the surface they were highly vulnerable to air attack. Nonetheless the OKM insisted. However, owing to yet another mechanical breakdown, Schütze had to abort the patrol and was thus unable to comply with the order. Limping home, in the Shetlands he sank his sixth ship, the 5,200-ton Danish tanker Chastine Maersk, giving him a grand total of 27,335 tons, a remarkable achievement for this unsafe and unreliable boat.
The OKM insisted that Dönitz provide the German ships in Vigo an escort. Accordingly, Dönitz assigned the chore to the other Type IX, U-41, commanded by Gustav-Adolf Mügler, making his second Atlantic patrol. While en route to Vigo, Mügler ran into a convoy in the Western Approaches. Pausing to attack, Mügler severely damaged the 8,000-ton Dutch tanker Ceronia and sank the 9,875-ton British freighter Beaverburn. The lone convoy escort, the destroyer Antelope, pounced on U-41, fixed her on sonar, and dropped depth charges. Nothing more was ever heard from U-41. She was the fourth of the eight Type IXs of the Hundius Flotilla to be lost, the third to be sunk by depth-charge attack.
Dönitz planned four minelaying missions for January, but only two Type VIIs, U-31 (Habekost) and U-34 (Rollmann), were seaworthy. As a result, one mission was scrubbed and another was assigned to the leading torpedo shooter, Herbert Schultze in the VIIB U-48. The three boats were to lay eight new, powerful TMC mines and carry six torpedoes. Neither Rollmann nor Schultze had laid a minefield; Habekost had laid the field in Loch Ewe that had damaged the battleship Nelson, a success still unknown to the Germans.
The two Type VIIs sailed first. On the way, Rollmann in U-34 attacked a 15,000-ton armed merchant ship with torpedoes, but they missed or malfunctioned. He then laid his mines in Falmouth. Habekost in U-31 returned to the dangerous waters of Loch Ewe. Either these two fields comprising sixteen mines were mislaid or the mines malfunctioned. They produced one sinking: the 7,800-ton British tanker Caroni River in Rollmann’s field at Falmouth.
After laying these fields, both boats patrolled the Western Approaches with torpedoes. Rollmann sank a 5,600-ton Greek freighter, but Habekost experienced repeated torpedo failures and sank nothing. Homebound, Habekost came upon two British battleships and a heavy cruiser, but he was out of torpedoes.
Sailing on the last day of January, Herbert Schultze in U-48 was assigned to lay his mines in the dangerous waters off the British naval base at Portland, in the English Channel. Schultze believed he laid all eight TMC mines in the correct place, but they produced no sinkings. He withdrew to the Western Approaches to hunt ships with his six torpedoes and promptly sank a 6,900-ton Dutch freighter.
Five boats sailed from Helgoland in February to conduct torpedo patrols in the Atlantic. These were the clumsy and cranky Type I, U-26, three Type VIIBs, and the now-famous Type IX, U-37, still commanded by the Hundius Flotilla chief Werner Hartmann, who preferred the sea, however cold and miserable, to a desk and who hungered to sink ships and win a Ritterkreuz.
Before going on to regular patrolling, Hartmann had to carry out a dangerous special mission. The task was to land in Ireland two Abwehr agents* who were to intensify anti-British sentiments. While passing outbound in the Orkneys and Shetlands, Hartmann got the patrol off to a promising start by sinking two ships (one British, one Norwegian) for 5,700 tons. Continuing south, on the night of February 8, he eased U-37 into Dingle Bay on the southwest coast of Ireland and put the two agents ashore. But all for naught. Within a few days, intelligence or police officers detected and arrested both agents.
That done, Hartmann received orders from Dönitz to carry out another special mission. B-dienst had developed information that the carrier Ark Royal and battle cruiser Renown were en route from the south Atlantic to Portsmouth, England, escorting the cruiser Exeter, which had been damaged in an engagement with the “pocket” battleship Admiral Graf Spee.† The OKM directed Dönitz to lay a submarine trap at the west end of the English Channel, using U-37 and Herbert Schultze’s U-48 and any and all other available boats.
Hartmann moved into a likely interception position, but Schultze ran across an outbound convoy and chased it 350 miles to the west. The chase netted Schultze three ships for 24,700 tons, including a 9,000-ton Dutch tanker, Den Haag, and the 12,300-ton British refrigerator ship Sultan Star, but he had no torpedoes left and he had no desire to return to the submarine trap merely to serve as a lookout for Hartmann. When Schultze returned to Germany, Dönitz first berated him for going too far west and leaving the trap, then praised him to high heavens. Schultze had not only planted a TMC minefield, but also had sunk four ships for 31,526 tons, raising his total confirmed score to sixteen ships for 109,200 tons. Schultze thus became the first skipper to sink 100,000 tons of enemy shipping. That feat earned him the coveted Ritterkreuz—the second such award after Prien’s.
The U-26, commanded by a new skipper, Heinz Scheringer, age thirty-two, from the duck U-13, attempted to join Hartmann in the submarine trap, but he was slowed by heavy seas and arrived too late. Neither U-37 nor U-26 found the task force. After being released from the trap, both boats sank two ships in the Western Approaches, then proceeded to their original destination off the Iberian Peninsula. Hartmann arrived there, but the U-26 incurred a mechanical breakdown and Scheringer was forced to abort. On the way home he sank a third ship, bringing his total to three ships for 10,500 tons.
The three VIIBs sailed from Helgoland last. Two of these, U-50 and U-54, were brand-new boats, rushed into service undertrained. The U-50, commanded by Max-Hermann Bauer, age twenty-seven, son of the famous World War I submariner and historian Hermann Bauer, from the duck U-18, was compelled by an oil leak to abort in the North Sea, but resailed a few days later. The U-54, commanded by Günter Kutschmann, age twenty-nine, disappeared without trace. It is thought that shortly after leaving Helgoland Kutschmann strayed off course and hit a German or a British mine in Helgoland Bight.* The U-53, commanded by a new skipper, Harald Grosse, age thirty-three (replacing Heinicke), was delayed by a leaky conning-tower hatch.
Bauer’s U-50 and Grosse’s U-53 finally proceeded to the Atlantic. Rounding the British Isles, Bauer sank a 1,900-ton Swede in the Orkneys, then a 5,000-ton Dutch vessel west of Ireland. At about the same time, northwest of Scotland, Grosse sank four ships (two Swedes, a Norwegian and a Dane) for 11,500 tons and believed he had sunk a fifth, the 8,000-ton British tanker Imperial Transport, but she limped into port. Eager to restore U-53’s lost honor, Grosse broke radio silence to boast that he had sunk five ships for 30,000 tons. Then both he and Bauer continued south to the Iberian Peninsula by independent routes.
By mid-February Dönitz believed that six boats were near or in “southern” waters. This number of boats offered another opportunity to attempt a pack attack on a convoy that B-dienst had reported. He therefore directed the senior captain, Hartmann in U-37, to assume tactical command. But unknown to either Dönitz or Hartmann, two boats had been lost (U-41 and U-54) and one (U-26) had aborted, leaving only three in those waters: Hartmann’s U-37, Bauer’s U-50, and Grosse’s U-53.
In an almost exact replication of the first wolf pack, which had been reduced from six boats to three, two of the three boats found the convoy and mounted a loosely coordinated attack. Hartmann in U-37 sank three freighters (one Greek, one French, one British) for 16,000 tons; Grosse shot at a French tanker, but his torpedoes prematured. By mistake, Grosse sank a prohibited neutral not in the convoy, the 2,140-ton Spanish freighter Banderas, unwisely sailing blacked out. Having expended all torpedoes, Hartmann in U-37 and Grosse in U-53 headed home.
Bauer in U-50 did not find the convoy. However, while patrolling alone off Lisbon, he found another. He sank two ships—a Dutch freighter and the 4,600-ton tanker British Endeavor—and pursued, but during the chase one of his diesels broke down. Unable to make repairs at sea, Bauer was forced to abort and head home in the wakes of U-37 and U-53.
While these three boats were inbound, news of the sinking of the prohibited Spanish vessel reached Berlin and Dönitz. The Spanish professed to be Furious. The sinking strained relations between Berlin and Madrid and jeopardized future clandestine refueling operations in Spanish ports. In his eagerness to restore U-53’s lost honor, ironically Grosse had again besmirched the boat.
The U-53 did not have to answer for this latest sin. In the early hours of February 24, while rounding the British Isles, she was lost. A lone British destroyer, Gurkha, picked her up in the moonlight shortly after midnight. Gurkha immediately turned to ram, but U-53, which was on an opposite course inside Gurkha’s turning circle, dived. Gurkha threw over a depth charge “to keep her down,” then obtained a “good” sonar contact and prepared for a proper attack. Gurkha made three passes over U-53, dropping thirteen depth charges set at 150 and 250 feet. While reloading for a fourth pass, Gurkha noted that the sonar echo “gradually faded away and was never heard again.” The U-53 disappeared without trace in water 1,800 feet deep. She was the fourth of the VIIBs of the Wegener Flotilla to fall and the third to leave no survivors. The loss of sister ships U-53, U-54, and U-55 within a period of four weeks—two on maiden patrols and all commanded by skippers making first patrols in VIIBs—did not go unremarked.
Werner Hartmann in U-37 again came home to rave reviews. He had successfully landed two agents in Ireland, dutifully set up the futile submarine trap for Ark Royal, and duplicated his score on his prior patrol by sinking eight ships (including a trawler) for a total of sixteen. This tied Herbert Schultze’s record for numbers of ships sunk, but not tonnage. Hartmann claimed 43,000 tons for this patrol, giving him 78,300 tons, but the true figure for the patrol was 24,539 tons, reducing his (confirmed) total to about 60,000 tons. Accepting Hartmann’s claims (“80,000 tons in two patrols”), Admiral Raeder sent him and his crew a telegram of congratulations.
Bauer in U-50 also received rave reviews for his maiden—but aborted—first patrol. He claimed sinking six ships for 36,000 tons. He either greatly exaggerated the tonnage or had torpedo failures. His confirmed sinkings were four ships for 16,000 tons.
Dönitz mounted four minelaying missions in February, all by Type VIIs of the Salzwedel Flotilla, finally out of the shipyards. Günter Kuhnke in U-28 laid eight TMC mines off the British naval base at Portsmouth and afterward sank two ships by torpedo (one Dutch and one Greek) for 11,200 tons. Otto Schuhart in U-29, granted a “second chance,” laid twelve TMBs in Bristol Channel and claimed sinking three British ships for 25,000 tons by torpedo on the way home. (Only two ships for 9,800 tons were confirmed in the postwar records.) This was success enough not only to warrant retaining his command but also to draw praise from the OKM. The U-32, with a new skipper, Hans Jenisch, age twenty-six (replacing Hans Büchel), who had sunk seven ships for 8,400 tons, including the destroyer Exmouth while commanding U-22, planted twelve TMBs in Liverpool. On the way to and from Liverpool, Jenisch attacked three ships, firing seven torpedoes. Five torpedoes malfunctioned and two missed, but he sank a 2,800-ton Swede with his deck gun.
These three minefields, planted at great risk, produced scant returns. Kuhnke’s TMCs off Portsmouth resulted in no sinkings.* Schuhart’s TMBs in Bristol Channel bagged only a small (710-ton) coaster, which should not have triggered a mine. Jenisch’s TMBs at Liverpool sank the only important ship: the 5,000-ton British freighter Counsellor.
The fourth—and riskiest—mine mission was assigned to von Dresky’s U-33. He was to plant eight TMC mines at the British naval base in the Firth of Clyde, where Büchel in U-32 had failed earlier. Von Dresky nosed submerged into the Firth of Clyde in the early hours of February 12. Moments later, an ASW patrol boat, the minesweeper Gleaner, detected U-33 by hydrophone. Seeing Gleaner’s searchlight sweeping the water, von Dresky mistook her for a heavy cruiser. Believing the “cruiser” might pass out to sea, he laid U-33 on the bottom at 183 feet to wait. Gleaner fixed U-33 on sonar and dropped six depth charges set for 150 feet, four of which exploded directly over U-33, pounding the boat and causing severe leaking.
The attack caught von Dresky by complete surprise. Believing the attacker to be a destroyer, his men urged him to get U-33 off the bottom and evade to sea, but von Dresky appeared to be paralyzed. Another five charges from Gleaner, which exploded close and increased the flooding, brought him to life. Believing the boat to be doomed, he ordered his men to surface, scuttle, and abandon ship. Since U-33 carried an Enigma† and could be salvaged, he distributed the Enigma rotors among the officers, instructing them to swim well away from the boat and discard them.
When U-33 surfaced, Gleaner spotted her at once, opened fire with her 4” gun, and turned to ram. However, when Gleaner’s captain saw the U-33 crew come on deck, arms raised in surrender, he checked fire after five rounds and lay to alongside U-33. Meanwhile, von Dresky ordered the engineer to set in motion the scuttling procedures. The first attempt failed but the second succeeded—trapping the engineer below. The U-33 plunged down by the bow, and the crew jumped into the frigid water. Von Dresky exhorted the men to keep together. Many, including von Dresky, died quickly of shock, exposure, or hypothermia. From a total crew of forty-two, only seventeen men, including three officers, lived to become POWs. The British recovered three Enigma rotors from the officers of U-33. These were helpful to the codebreakers at Bletchley Park but not sufficiently so to penetrate naval Enigma.
Dönitz knew at once that U-33 was lost and the minelaying at the Firth of Clyde had failed for the second time. His source was B-dienst, which, remarkably, intercepted three signals from Gleaner. The first was an alarm at 0525, reporting U-33 to be on the surface; the second, at 0530, was a notice stating that the U-33 crew was surrendering; and the third, at 0545, was a request for assistance in rescuing the crew.
Counting the seven mining missions, Dönitz had mounted eighteen patrols to the Atlantic in the months of January and February, 1940. Five of the eighteen boats had been lost (U-33, U-41, U-53, U-54, U-55). Three (U-25, U-50, U-51) had aborted with mechanical defects. Yet in spite of torpedo and mine problems and unfavorable weather conditions, the eighteen boats had sunk by torpedo or mine fifty-eight ships for 233,496 tons, almost all of them sailing alone. This was an average of 3.2 ships sunk per boat per patrol, a significant improvement over the averages for the earlier months. On March 1, the six leading skippers in tonnage sunk were Schultze, Prien, Hartmann, Schuhart, Rollmann, and Lemp.
When the surviving February boats returned from the Atlantic, Dönitz had galvanizing news. Hitler had ordered the military conquest of Norway (and Denmark), to take place anytime after March 10. All available U-boats, including ducks, were to participate. Commencing March 1, the U-boat war against shipping in the Atlantic was suspended indefinitely.
The withdrawal of the Atlantic U-boats for operations in Norway provides a convenient milepost for assessing the results of the U-boat campaign in the first seven months of the war, to April 1, 1940. That assessment can best be made by a careful study of a host of statistics that challenge some and exasperate others, then as now. In brief:
• All U-boats (oceangoing and ducks) in all areas sank by torpedo, gun, mine, and demolition a total of 277 ships for about 974,000 tons, including twenty-six trawlers, almost all of them sailing alone or out of convoy.* In addition, the oceangoing boats captured four prizes. The North Sea ducks sank 41 percent of all the ships (113) and about 25 percent of the tonnage (238,000).
• Of the 277 ships sunk, 118 (43 percent) were British, including the twenty-six trawlers. The loss of ninety-two British ships other than trawlers in seven months amounted to about 3 percent of the 3,000 vessels of the oceangoing British merchant fleet. In the same seven months, the British captured, bought, or chartered ninety-two ships from foreign sources, offsetting the British losses to U- boats. Moreover, in the same period, British shipyards produced about 700,000 tons of new shipping, much of it for the merchant marine. Thus, in the first seven months of war, the British merchant marine grew, rather than shrank.
• Of the 277 ships sunk by U-boats, surprisingly few were tankers: only twenty-three of about 170,000 tons. Of these, fourteen for about 100,000 tons were British-owned. The other nine were French, Norwegian, Danish, Swedish, or Dutch. The British tanker losses were more than offset by captures or seizures, by new construction, and by purchase and charter of foreign vessels. Thus there was a net gain in the British-controlled tanker fleet.*
• Notwithstanding the growth of the merchant fleet in these seven months, British imports fell 25 percent, from a rate of about 60 million tons a year to about 45 million tons a year. The drop was caused by convoying. It was not a drop of one-third, as Churchill predicted it would be, but about one-quarter. The drop was inconvenient and led to belt-tightening and scattered deprivation, but it was nowhere near a threat to Britain’s survival.
• In the same seven months, U-boat losses were heavy, a total of seventeen (30 percent of the force) to all causes: four ducks, eight VIIs and five IXs, manned by about 650 submariners. The loss of oceangoing boats was offset in part by new construction: eight boats, of which four were VIIs and four were IXs. Thus the total number of oceangoing U-boats of the Atlantic force decreased from twenty-seven to twenty-two, of which two, U-25 and U-26, were marginal and several others were out of action for extended repairs. The addition of the marginal Turkish boat, U-A, raised the Atlantic force to twenty-three oceangoing boats by the end of March 1940.
To this point in the U-boat war, both London and Berlin claimed “victory.” However, the figures suggest something like a draw. In any case, the U-boats had yet to pose a serious threat to British maritime assets. The real U-boat peril—if it ever fully materialized—lay not in the summer of 1940 as Churchill projected but in the far distant future, 1942 and beyond. Moreover, contrary to Churchill’s assertions, U-boat crews had not waged war barbarically or murderously or with callous disregard for the safety of enemy mariners. For the most part, the Germans had conducted submarine warfare in a fair—and at times even chivalrous—manner. As Dönitz was to stress again and again, he ran “a clean firm” and he intended it to stay that way.
One important factor in this naval war was the increasingly anti-German, pro-British attitude of President Roosevelt. It was he who had engineered the relaxation of the Neutrality Act, which enabled American firms to sell arms to the British and French. He had also turned a blind eye to the transfer of American tankers to “Panamanian” registry, so that they could transport oil directly into the declared war zones. In addition, Roosevelt had masterminded the “Declaration of Panama” (October 2, 1939), a conference at which twenty-one American republics (not including Argentina) established a Western Hemisphere “Security Zone” that barred belligerents from “conducting warlike operations.” Moreover, Roosevelt had directed the U.S. Navy to put in place a “Neutrality Patrol” to enforce the declaration. Not least, Roosevelt, anticipating the forthcoming need for merchant shipping, had again urged Jerry Land at the Maritime Commission to increase significantly America’s cargo and tanker shipbuilding capacity.