Figure 1.--The great naval battles of World War II were fought in the Pacific, but had virtually no impact on the outcome of the War. The Battle of the Atlantic in contrast was central. Not only was America able to commit its manpower and vast indstrial power to the defeat of NAZI Grmany, but was able to use it to bolser the ed Army in he East. And thanks to Adm. King, this was done while at the same time that the U.S. Pacific Fleet destoying the Japanese Imperial Navy and the country's ability to make War.

"The political and miltary leadership of Germany -- reared in continetral concepts, and caught in them -- did not recognize the decisive importance of the naval war to grand strategy. The lack of undrstanding was one of the fundamental reasons for the political and strategic errors committed by the German state and war commands."

--Adm. Karl Dönitz, Kriegsmarine U-boat Commander, 1968. Adm. Raeder would have argued that Dönitz committed a central strategic error by arguing for war with America and failed to recognize the importance of the vast industrial strength of the United States.

World War II began when the aging German cruiser SMS Schleswig-Holstein opened fire on Polish forces in Danzig (Gdansk) in the Baltic -- 4:47 AM September 1, 1939. Two days later, The U-30 torpedoed the liner SS Athenia (September 3). This marked the beginning of the Battle of the Atlantic. Now the great naval battle of the War would be fought in the Pacific, but America and Britain adopted a Germany first strategy--for good reason. NAZI Germany with its industrial and technological prowess, despite Pearl Harbor, was the real danger. And the Battle of the Atlantic would settle the central question of the War--could America with its immense industrial power get its men and equipment to Europe and wage war on the NAZI Germany? There were two phases to the Battle of the Atlantic. The first phase of the battle witnessed considerable German successes, especially Adm. Dönitz's U-boat fleet. The German admiralty planned a commerce war against Britain with both surface vessels and U-boats. The problem for the German Navy was that their surface vessels failed. Adm. Dönitz's U boats achieved some successes, only Dönitz began the War with only a handful of U-boats so he impact was limited. Hitler then ordered priority to U-boat construction. So by the time of Pearl Harbor, Dönitz was amassing a growing U-boat fleet. The second phase of the Battle was fought after Pearl Harbor (December 1941). This meant that the full force of American industry was now going to be deployed against Germany. Adm. Dönitz but not Adm. Raeder was urging this, not calculating the force of American industry. Naval wars are by definition industrial wars. And once American industry was mobilized for war--the Germany Navy had no chance of winning the War. Again Dönitz with his U-boat fleet scored major victories (1942). With American industry fully geared for war, the Germany Navy had no potential for victory and the U-boats became the hunted rather than the hunter (1943). Theonce feared U-boats rge ferce with the higest casulty rate of the EWar. And there was nothing to stop Allied shipping from delivering American men and equipment from entering the fight against the NAZI tyranny. At the same time, German spending on the War in the West, most naval and air operations, meant that vast amounts of German industrial output was diverted from the all-important Ostkrieg. While the War began with naval gunfre fom an obsolete German World War I-era cruser, it ended beneth the big but silent guns of the very modern USS Missouri (September 1945)

World War II (September 1939)

Hitler launched World War II with the Bliztkrieg on Poland (September 1, 1939). German planning had originally seen a later ate for the War. British and French weakness at Munich had apparently convinced Hitler that they would not risk war over Poland. Ironically the first shots of the War were fired by the aging battle ship Schleswig-Holstein at Polish installations at Danzig. Poland was defeated within weeks, but the Kriegsmarine was unprepared for the War. Military strategists argue whether Hitler should have waited. In many ways Germany was not yet ready for war. This was especially true for the Kriegsmarine. Both Britain and France by 1939 had begun to rearm and in particular build airplanes and but none for America. Thus war in 1939 came at a time before Britain and France had fully rearmed. Another factor was economics. Germany as a result of its armament program was virtually bankrupt. Germany needed war booty to help pay for the high cost of its military armament program. Britain wold soon be bankrupt, but the United States through Lend Lease wrote Britain a blank check to stay in the War making it impossible for Germany to defeat Britain. The great naval battles of World War II were fought in the Pacific, but had virtually no impact on the outcome of the War. The Battle of the Atlantic in contrast was central.

First Phase (1939-41)

The Germans with U-boats, surface fleet, and long range aircraft hoped to cut off Britain from its Empire and supply from the United States. The U-boat was a particularly attractive weapon, because a U-boat could be built in 6 months at a fraction of the cost of a surface unit. The Germans conceived of using their available force as commerce raiders, to prevent supplies from America and the Dominions from reaching Britain and France. Dönitz had 30 U-boats at sea when the War began. Plan Z had called for having 100 U-boats at sea, but Hitler had begun the War before the Kriegsmarine was ready. Döenitz at the time had 46 U-boats, but only 22 capable of long range operations. The success of the U-boats soon Karl Dönietz and established the U-boat fleet as the darlings of the German War effort. There has always been a strong isolationist streak in American political life. Americans separated by two great oceans have since the Revolution seen ourselves as different and apart from the rest of the World. President Roosevelt begun a campaign to rearm America. A few days after the fall of France in 1940, a shocked American Congress approved the Naval Construction Act. Isolationist leaders opposed any war. The German invasion of Norway was another stunning success. It gave the Germans control of Norwegian resources, especially iron ore. It also made it impossible for the Royal Navy to bottle up the U-boats in the North Sea. This success, however, came at a high cost to the Kriegsmarine. Virtually its entire destroyer force was sunk landing troops and supplies The fall of France in June 1940 tremendously increased the effectiveness of the German naval campaign, providing indispensable French Atlantic ports. After France fell, the Royal Navy stood alone against the German and Italian navies. The immediate naval concern was the French fleet. Churchill's most difficult decision after France fell was the order he gave to neutralize the French fleet. The British needed deliveries of about 1,000 merchant ships monthly to stay in the war. Based on their World War I experience the British armed their merchant men and introduced a new convoy system. The NAZI defeat of France proved to be a major advantage for the Kreiegsmarine. Dönitz now had access to the French Atlantic ports. his mean that the U-boats no longer had to expose themselves to the British North Sea defenses based around Scappa Flow. It also mean that the U-boats could spend more time on combat missions in the Atlantic as less time was needed to move back and fort from home bases. In addition the Germans could use their long-range Condor bombers for reconnaissance flights to help locate the convoys. The summer of 1940 became known by the U-boaters as "The Happy Time". One British convoy sailing in October with 35 merchantmen from Newfoundland was savaged by the U-boats, 19 merchantmen were sunk. Almost from the beginning of war in Europe, President Roosevelt began what was to become an undeclared war with Germany in the North Atlantic. The first tentative step was naval patrols to to prevent belligerent ships from U.S. waters. At first the American role was limited, but as the situation worsened and the German's expanded the U-boat fleet, the American role expanded. The Royal Navy was ill prepared for the war. Losses to the u-boats were severe, despite the fact the Keiegsmarine began the War with only a small force. Months before American entered the War, the U.S. Navy was involved in a full-scale shooting war to protect the convoys needed to keep Britain in the War. A great deal has been written about the British cracking of the German enigma codes and the the impact on the War, especially the campaign against the U-boats in the North Atlantic. Less well known is that the Germans succeeded in breaking the British naval convoy code. The the German U-boat operations proved highly effective, despite the fact that Hitler launched the War years before the Kriegsmarine was prepared. Dönietz began the War with only 57 U-boats. he was convinced that with enough U-boats he could knock Britain out of the War by cutting her off from her overseas Dominions and America. The strength of the U-boat fleet steadily grew. The threat was so severe that President Roosevelt at considerable political danger confronted the isolationists while America was still neutral and provide assistance even destroyers to protect convoys. The German u-boat campaign succeeded in sinking substantial numbers of Allied shipping. For a time the U-boats were even winning a war of attrition. Despite those losses, the Allies ended the War with a larger merchant fleet than at the onset of War. The reason was a revolution in ship building, one of the most significant developments in the War--the Liberty Ships.

Pearl Harbor (December 1941)

The Japanese attack on Pearl Harbor (December 7, 1941) brought America into the War. It was a stunning success for the Japanese and perhaps the greatest strategic blunder in the history of warfare. It came at the same time that the Red Army launched an offensive against the Wehrmacht at the gates of Moscow. The Axis alliance was a defensive alliance which would have required Germany to go to war against a country which attacked Japan, but not with a country which Japan attacked. Even so, Hitler declared war on the United States. This solved a problem Roosevelt faced, how to bring America into the European War when America had been attacked by the Japanese. No one knows why Hitler declared war on America. Certainly the American attacks on U-boats had angered him. Perhaps he thought that Roosevelt was about to declare war and he wanted to beat him to this step. We suspect that Hitler, stunned by the reversals in Russia, felt compelled to take some offensive action to regain control of events. The action, however, was a huge strategic blunder. One wonders how having failed to subdue Britain and now mired in a punishing winter campaign in Russia, he could have decided to declare war on the greatest industrial power in the world. Roosevelt may well have engineered a declaration of war, but it would have been a difficult measure and he would have brought along a less unified American public.

Second Phase (1942-45)

Dönitz after the declaration of War dispatched a U-boat force to the coast of America (December 1941). The U.S. Navy was unprepared and coastal shipping was devastated. The success of Germany's U-boat campaign was in large measure due to tactics developed by Dönitz who conceived of the wolf pack. Dönitz was a master technician, but he was often dismissive of technology. After Operation Drumbeat, Dönitz moved the U-boat campaign into the mid-Atlantic beyond the reach of aerial patrols. Given the success of the U-boats, the Germans stepped up production. The principal German tactic was the Wolf pack, Even before America entered the War, the U.S. Navy was deployed in the North Atlantic to protect British convoys. Anglo-American naval and scientific cooperation resulted in the defeat of the U-boat campaign by 1943. German U-boats in early 1943 continued sinking substantial numbers of merchant vessels. The British food supply in early 1943 was down to a few months. The U-boats sank about 100 merchant vessels in 1943. That was a rate that could not be replaced even by the Liberty Ships. U-boat sin kings were also increasing. A major engagement was fought out in March involving 80 merchants, 20 escort vessels, 44 U-bots and numerous aircraft. The engagements on the North Atlantic were no longer one-sided. The Allied sank 15 U-boats in April 1943. More than in the past, but still not enough to deter the Germans. World War II turned against the NAZIs during late 1942 and early 1943. The war at sea turned in May 1943--known as Black May by the U-boat men. In that month, the building Allied naval strength in the Atlantic and widening technical superiority succeeded in sinking 41 U-boats. The U-boats were no longer the hunters, but the hunted. Increasingly after May there was less and less a chance of a U-boat returning from a cruise. Dönitz had to break off the campaign in the North Atlantic. The Germans by the end of 1943 had built 442 U-boats, had lost 245 U-boats. More than any other factor, it was the expanding Allied air cover which doomed the NAZI U-boat campaign. The United States built more than 100 aircraft carriers during World War II. The Anglo-American victory in the Battle of the Atlantic not only allowed Britain to survive but allowed it to actively pursue the War. It also allowed America to assembled massive force of men and supplies in England that in 1944 was unleashed on Hitler's Atlantic Wall. In the end, surviving on U-boats was one of the most dangerous assignments of the War. Three-quarters of the U-boat fleet was sunk at sea and about 70 percent of the U-boat crews killed. In all the Allies sank 785 U-boats. To this day, 68 U-boats are unaccounted for. The Germans were working on a vastly improved U-boat. The new u-boats were great improvements and after the war became the nucleus of the Soviet naval submarine fleet.

Created: 5:34 PM 10/25/2025
Last updated: 5:34 PM 10/25/2025