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cargo vessels World War II -- technology naval campaigns ship types
World War II Naval Ship Types: Cargo Vessels
Figure 1.--The United States Navy launched an undeclared naval war against the German U-boats in the North Atlantic (June 1941). This was several months before war was declared. Hitler was infuriated but ordered Admiral D�nitz to avoid attacks on American shipping. The U.S. Navy was not yet capable of dealing with the U-boat menace. Admiral Dönitz immediately ordered Operation Drumbeat which commenced (January 1942) and brought the War to American shores in a spectacular way. The Kreigsmarine did not, however, have sufficent long range U-boats (Type IX) for an extended campaign. The principal attacks continued only for a few weeks (until early-February). Attacks contiunued at a reduced level until the long-range U-boats were finally withdrawn (July 1941). By this time the furror had largely died down. (Mothers would have probably not have let the boys go a few months earlier.) Here Boy Scouts on the sail ship 'Ida May' watche a tanker pass by during late-July 1942. The Scout who took the photograph wrote on the back, "One of our tankers passes the 'Ida May' on the starboard side." It was American oil and tankers like this that fueled the war effort of the Western Allies.
The carriers, battleships, and other fighting ships of combatant navies attract the greatest attention in World War II histories. Ironically the most important vessels were the dowdy cargo/merchant vessels including the tankers. The fighting ships had one primary purpose, the hold the sea lanes open for your cargo vessels or close them for the cargo vessels of your enemy. This is what the fundamental struggle in the key World War II naval campaign--the Battle of the Atlantic. It was according to Primeminister Churchill, the struggle that worried him the most. The Allies approach to this struggle was to steadily increase the escort and U-boat killing capacity of their navies. Surprisingly the Pacific, the Japanese built a large submarine fleet, but did not use it for this purpose, but rather most were tied up in hunting naval combat vessels and supplying cut off island garrisons. The second Allied effort was to increase construction of merchant vessels. Here the American Liberty Ships proved that ships could be built faster than the U-boats could sink them even before the tide turned in the North Atlantic. The victory of the Allied fleets (American, British, and Canadian) ensured that the output of American factories and farms as well as oilfields not only reached the American fighting man, but also as part of Lend Lease the fighting men of its allies. The first American offensive in the War was fought over Guadalcanal with the purpose of keeping the sea lanes to Australia open. The Japanese gave considerable thought to their World War II Pacific campaigns. One element not considered was the greatly expanded merchant (maru) fleet needed to fight the Pacific War. And unlike the United States, the Japanese did not have the capacity to significantly increase the construction of merchant vessels, especially when the Imperial Navy began to sustain significant losses. Japan had gone to War to secure the critical material of the Southern Resource Zone (SRZ). Not only did the maru fleet prove inadequate for supplying the outposts spread all over the Pacific and carrying the materials from the SRZ back to the Home Islands, but by mid-1944, American submariners assisted by Ultra had virtually destroyed the maru fleet. Besides escorting or attacking cargo vessels, the only other important naval function was launching amphibious invasions, but even this required the cargo vessels to supply those invasions.
