Military history


Most accounts of the German U-boat campaign in American waters in the spring of 1942 describe that operation in isolation. This depiction leads invariably to an absurdly incomplete and even distorted picture of American counteractions.

When the U-boat campaign off the United States East Coast reached its peak in April 1942, the following major naval operations were in progress or afoot worldwide.

The Japanese in the Indian Ocean.

In the first week of April, powerful Japanese naval and amphibious forces sailed from Malaysia into the Bay of Bengal. A covering force of five carriers, four battleships, and supporting vessels challenged the newly arrived but weak British Eastern Fleet (three carriers, five old battleships) based at Ceylon. The Japanese sank the old, small carrier Hermes, the cruisers Cornwall and Dorsetshire, the destroyers Tenedos and Vampire, the corvette Hollyhock, and two fleet tankers, and forced the British Eastern Fleet to retreat 3,000 miles west to Kilindini, Kenya (near Mombasa) on the east coast of Africa. During this foray, various Japanese warships and aircraft sank in addition twenty-three British-controlled merchant ships for about 112,000 tons and damaged others. Japanese submarines sank another half dozen merchant ships. Japanese amphibious forces landed at Rangoon, Burma, and on the Andaman Islands, posing a threat to India.

Churchill sent a series of urgent appeals to Roosevelt for assistance in this theater. Among other proposals he suggested that the carrier Ranger and battleship North Carolina of the Atlantic Fleet might join the British Eastern Fleet or, alternately, that North Carolina join the battleship Washington on anti-Tirpitz duty in Scapa Flow, thereby releasing the battleship Duke of York to join the Eastern Fleet. Admiral King rejected these proposals, suggesting instead that American heavy bombers be rushed to the Indian Ocean area.

Churchill also proposed that the American Pacific Fleet consider making a threatening gesture of some kind which might draw these Japanese naval forces back from the Bay of Bengal into the Pacific. Unknown to Churchill, at that time the American carriers Hornet and Enterprise, plus support forces, were boldly approaching the Japanese home islands to launch the “Doolittle raid,” which, by uncanny coincidence, was exactly the kind of naval action Churchill sought to relieve pressures in the Indian Ocean. Although the Japanese naval forces withdrew from the Bay of Bengal a few days before the Doolittle raid was carried out April 18, the raid, too often casually dismissed as a stunt, was to profoundly influence the course of the Pacific war in the two months ahead.

The British in Madagascar.

At about this same time, British naval and amphibious forces massed in Cape Town and Durban, South Africa, to invade Vichy Madagascar, thereby denying the Japanese the possibility of a collaborative occupation, a la Indochina. As related, it was this operation (Ironclad) that drew important forces from the British Force H at Gibraltar, forcing a dilution of the Home Fleet at Scapa Flow to reinforce Force H at Gibraltar and the transfer of American Task Force 39 (99) (carrier Wasp, battleship Washington, etc.) to Scapa Flow to reinforce the Home Fleet on anti-Tirpitz duty.

The lead ships of the British invasion force sailed from Durban to Madagascar on April 25. Elements of the British Eastern Fleet sailed from Kilindini in support. The British hoped that Vichy French forces on Madagascar would not oppose the landing, which took place on May 5, but the French mounted a spirited defense for several days before they were overwhelmed.

To speed up augmentation of Allied airpower in the Indian Ocean area, Churchill urgently requested that Roosevelt ferry fighter planes to West Africa. When Roosevelt acceded to this request, King assigned the task to the carrier Ranger. Loaded with sixty-eight Curtiss P-40 Warhawk aircraft, Ranger sailed from Rhode Island on April 22, escorted by the cruiser Augusta and five destroyers.* The aircraft flew off Ranger on May 10, landing at Accra, Ghana (on the Gold Coast). From there, they flew on to India. Ranger and escorts returned to the United States.

It is customary for historians—especially British historians—to portray Admiral King at this time as fixated on Pacific operations to the neglect of the U-boat war in the Atlantic. However, these same historians invariably fail to note the British fixation on Indian Ocean operations at this time and the consequent drain of Allied naval assets from the Atlantic.


The Luftwaffe in the Mediterranean Basin supporting Rommel’s Afrika Korps launched a series of brutal bombing raids on the British island of Malta at this time, viewed by many Allied war planners as a prelude to an airborne invasion. Believing Malta to be a strategic and psychological asset of incalculable value, Churchill insisted that heroic measures be made to deny it to the Germans, assuring the Maltese that “the Navy will never abandon Malta.”

The defense of Malta thus became another heavy drain on Allied naval assets in the Atlantic. The Luftwaffe and Italian air and naval forces inflicted severe damage on British convoys attempting to fight through to the island. To reinforce the thin British air forces on Malta, Churchill asked Roosevelt on March 31 if the carrier Wasp, en route to Scapa Flow in Task Force 39 (99), could fly off Spitfires for Malta. Although Admiral King was not keen to risk a new fleet carrier in this graveyard of warships, in due course he relented and Wasp took on forty-seven Spitfires in the Firth of Clyde and sailed to the Mediterranean on April 14.

Escorted by the battle cruiser Renown, cruisers Charybdis and Cairo, and a flock of destroyers, including the American Lang and Madison, Wasp slipped through the Gibraltar Strait unseen and launched the Spitfires on April 20. In the first week of May, Wasp, with American destroyers Lang and Sterett, made a second trip from the Clyde to the Mediterranean in company with the British carrier Eagle and escorts. On May 9, Wasp flew off another forty-seven Spitfires to Malta.

The Murmansk Run.

In response to a direct order from Hitler, Tirpitz, the “pocket” battleship Admiral Scheer, the heavy cruiser Hipper, supporting destroyers, and the Luftwaffe threatened Allied PQ and QP convoys en route from Iceland to Murmansk and return. Tirpitz made one sortie in March—her first combat mission—but it was a complete failure. However, owing to her presence and that of Admiral Scheer and Hipper, the British were compelled to sail heavy ships of the Home Fleet to provide cover for the Murmansk convoys.

As the periods of daylight in the Arctic became longer in April, the risk of German attacks on Murmansk convoys increased. This seasonal factor led Admiral Pound to suggest to the War Cabinet that the Murmansk convoys might not be worth the risk. But in view of the impending German spring offensive against the Red Army, Roosevelt insisted it was not only impolitic but also dangerous to suspend the Murmansk convoys. He not only refused to consider a suspension but also demanded that the Admiralty increase the size and frequency of Murmansk convoys to clear out 107 merchant ships loading or loaded for Murmansk, which were backing up in Iceland and elsewhere.

Reflecting the views of the Admiralty, Churchill parried. The Murmansk run had cost the Royal Navy the cruisers Trinidad, damaged, and Edinburgh, sunk.* Besides that, the battleship King George V of the Home Fleet had been damaged in a horrendous collision with the destroyer Punjabi, which broke in half and sank. The battleship had to have extensive repairs before she could again provide cover for a Murmansk convoy, The best Churchill could promise was the sailing of three PQ convoys of twenty-five to thirty-five ships every two months. Based on this lukewarm projection, Roosevelt and King rightly concluded that to keep promises made to Stalin, ships of the American task force temporarily at Scapa Flow would have to be assigned to escort Murmansk convoys. Not without reason, King began to suspect that the goal of the Admiralty was to pull American naval assets ever deeper into the multifarious British naval schemes, however ill-advised those schemes (such as Madagascar and Malta) seemed to the Americans.


Uppermost on the American list of naval operations—or possible operations—in early April was Sledgehammer, the emergency invasion of Occupied France, should the Red Army collapse under the weight of the German spring offensive. On April 8, Army Chief of Staff George Marshall and Harry Hopkins arrived by air in London to obtain British approval for Sledgehammer in 1942 and to discuss the larger alternative, Roundup, in 1943.

Owing to the impending Doolittle air raid on Japan and to cryptographic intelligence that indicated another big—perhaps even decisive—naval battle brewing in the Pacific, King remained in Washington. However, it bears repeating that King fully approved of Sledgehammer (and Roundup) in part as a means of evicting German U-boats from French bases and in part to curb what he viewed as the British peripheral operations in the Mediterranean Basin and Indian Ocean, and to keep the Admiralty focused to the greatest extent possible on operations the Americans believed to be most likely to lead to an early defeat of Germany.

The British opposed both Sledgehammer and Roundup but deliberately and deceptively gave Marshall and Hopkins the impression that they approved Roundup so that the Americans would not abandon the campaign against Germany and go all-out after Japan. In fact, what the British sought was a revival of the canceled Gymnast, the invasion of Vichy French Northwest Africa, to trap Rommel’s Afrika Korps between Gymnast forces and the British Eighth Army.

While Marshall and Hopkins were in London, Churchill and First Sea Lord Pound repeatedly drew attention to the heavy Allied shipping losses to U-boats on the United States Eastern Seaboard, and continued to insist that the Americans initiate convoying in that area. Doubtless Marshall agreed with that line—it was the American Army line as well—and perhaps he influenced Hopkins, who on April 14 cabled President Roosevelt to urge that coastal convoying be initiated. In part, Hopkins said:

Shipping losses in western North Atlantic during period January 12th to April 12th of United Nations tonnage are 1,200,000 gross tons. During the past week we have lost in the same area 150,000 tons of which 106,000 tons were tankers. It seems to me that the ships we are losing are in the main far more important than the cargoes. We are going to need all of these ships desperately in the next few months.

British are agreeable to reducing stocks [i.e., imports] to make sure that ships are not sunk and it seems to me that we should be able to do the same thing. In other words, unless the cargoes are absolutely essential the ships should not be permitted to sail until our new [convoy] scheme comes into operation next month. I doubt very much that anything short of convoy is going to do this job and risking further ships without reasonably sure protection is the wrong policy. I should feel somewhat differently about this if every cargo was absolutely essential to the war effort during the next few weeks, but if the British can give up cargoes temporarily, I am sure we can….

I cannot impress upon you too strongly the concern which all here [in London] have in regard to this matter. This is only natural because this island is so dependent on imports and they realize full well the significance of these sinkings to the future of the war. I need not dwell on the importance of every possible ship to us during the coming months. I had planned to postpone a discussion of this until I could see you, but the matter seems to me to be of such urgency that I decided to take it [up] by cable.

Doubtless this provocative cable dismayed King, who was at that very time doing everything in his power, to meet the other multifarious British naval requests and to initiate convoying in the Eastern Sea Frontier. Moreover, as he cabled Hopkins (for delivery to Churchill) on April 16, King had already decided to suspend tanker sailings:

Conference of representatives of agencies concerned have reached decision to lay up tankers operating on Atlantic coast for a period, depending upon availability of more protection. Opportunity will be taken to arm ships as rapidly as possible. Action on dry cargo ships under consideration….

From that day, April 16, to April 29, a period of two weeks, all tankers under American control in the Western Hemisphere remained in ports. On April 18, the British likewise suspended tanker sailings in the Gulf of Mexico and Caribbean, but after a change in routing plans resumed sailings six days later, April 23. Under the new routing plans, British-controlled tankers were to sail to Trinidad, thence due east across the Atlantic to Freetown, and from that place to the British Isles in Sierra Leone convoys.

In a separate message to Roosevelt, Churchill expressed delight and satisfaction over his meetings with Marshall, Hopkins, and others, and regret that Admiral King had not come over as well. “We have established the most intimate contacts with the United States Army and Air Force [sic] but as Harry will tell you, we are not nearly so closely linked up on the Naval side. Yet all depends on this being successfully handled in unison. I am therefore sending the First Sea Lord [Pound] back with General Marshall and Harry in order that he may discuss with you and Admiral King the whole position and make long-term plans….”

The American party and First Sea Lord Pound departed the British Isles by air on April 18. Pound remained in Washington for a week, April 20 to April 26, conferring with Roosevelt, King, and others on the many naval matters on the agenda.

Pound and others in the British naval party found Admiral King and his senior aides preoccupied with the Pacific. British historians and writers depict this preoccupation as some sort of chicanery or disloyalty or, in view of the U-boat threat in the Atlantic, scandalous stupidity.

In fact, King had every justification for being preoccupied with the Pacific that week. Allied codebreakers, who had partially broken back into the latest variation of the Japanese naval code, JN 25, had picked up clues which indicated that the Japanese might be planning an amphibious attack in “late April” on Port Moresby, New Guinea, and/or the islands of New Caledonia and Fiji. The capture of Port Moresby would provide the Japanese an ideal staging base for an invasion of Australia, which had been designated as the main Allied stronghold in the southwest Pacific. The capture of New Caledonia and/or Fiji would put the Japanese in position to cut the Allied line of communication to Australia, which, under terms of the Arcadia conference, the Americans were pledged to keep open. Beyond that, on April 18, American naval codebreakers had found hints in the partially decrypted radio traffic that the Japanese might be planning another big assault on Hawaii or perhaps even California(!).

The major American naval forces in the Pacific at that time were ill-disposed to thwart Japanese moves in the southwest Pacific. The carriers Hornet and Enterprise and supporting vessels were only just beginning the return voyage from the April 18 Doolittle air raid on Japan. There was no way they could replenish in time to reinforce Allied naval forces in the southwest Pacific by “late April.” If the Japanese were to be thwarted in that area, the carriers Lexington and Yorktown and supporting forces, including land-based aircraft, would have to do the job.*

There was little debate in Washington over whether or not an attempt should be made to thwart the Japanese in the southwest Pacific. Another major setback in the Pacific, such as the loss of Port Moresby or New Caledonia or Fiji or even Australia, combined with the fall of Bataan and Corregidor would be devastating. It might topple the Churchill government and even lead to an impeachment of President Roosevelt. At the least, such a setback would again besmirch the Navy’s reputation.

The situation was so fraught with danger that King insisted on a face-to-face meeting with Pacific Fleet commander Chester Nimitz at a mutually convenient site. Thus, on April 24, when First Sea Lord Pound and his party were settling in for sweeping and prolonged strategy talks, King and his senior advisers abruptly left Washington to meet with Nimitz and his senior advisers, April 25 to April 27, in San Francisco. There the principals and their staffs hammered out a plan for a precious few American capital ships to battle Japanese capital ships on the high seas for the first time in the war.

Left high and dry in Washington, it is little wonder that First Sea Lord Pound and his delegates felt snubbed by Admiral King and wrongly came away convinced that King was much too narrowly preoccupied with the Pacific. Nonetheless, Pound’s conferences with Roosevelt and King’s subordinates usefully cleared the air on a number of important naval issues, including the impending start-up of convoys in all waters of North America which were accessible to U-boats.

The convoy routes in American waters, to be initiated in the first two weeks of May, if possible, were:

Key West-Norfolk-Key West.

This route was to be protected by forty-three warships organized into five escort groups and aircraft. The ships were to include nine American four-stack destroyers, to be permanently assigned to the Eastern Sea Frontier in April; five of the ten British corvettes that finally arrived in April§twelve of the fourteen British ASW trawlers that completed voyage repairs and came into service in April; two big gunboats (ex-yachts Plymouth and St. Augustine); nine new 173-foot PCs; four 165-foot Coast Guard cutters (Argo, Calypso, Dione, Icarus) and two World War I Eagle subchasers. Eight other vessels (four 165-foot Coast Guard cutters; two British trawlers; two Eagles) were to serve as a reserve force. Fifty-seven small craft along the route were to provide ASW patrols and rescue.


This route was to be protected by the Canadian WLEF, composed of four-stack destroyers and corvettes.

A direct Halifax-Caribbean-Halifax route.

To be utilized exclusively for Canadian oil imports and protected by one Canadian group (four corvettes) withdrawn from the MOEF, this route was to commence operations May 17. Initially the convoys were to be comprised of six tankers sailing every fourteen days, but by June 8 the sailings had increased to one every ten days, directly from Aruba, bypassing Trinidad.


This British tanker “shuttle” route, which commenced operations on May 18, was to be protected by one British escort group withdrawn from the MOEF. After reaching Trinidad, loaded British tankers were to sail independently from Trinidad east to Freetown, thence to the British Isles in Sierra Leone convoys, thereby bypassing the hazardous American Eastern Seaboard. Tankers returning to Trinidad to join the reverse convoys to Aruba were to sail in Outbound South convoys.


Several other routes in the Gulf of Mexico and the Caribbean were to be established as escorts became available.

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