CHAPTER I 



INTRODUCTION 



Importanc e of Subsurface Warfare . 



Twice in two World Wars the submarines of an aggressive 

 enemy brought the United States and her allies to the brink of 

 defeat „ 



In both World War I and World War II, the Allies succeeded 

 only by the narrowest of margins in maintaining their vital 

 lines of supply by sea„ 



During the approximately 51 months of World War I, enemy 

 submarines sank some 4,837 merchant vessels, totaling 11, 135,000 

 gross tons. During the approximately 7/2 months of World War II, 

 enemy submarines sank 2,753 merchant vessels, totaling 14, 557,000 

 gross tons, a total for the two wars of 7,590 ships of 25,692,000 

 gross tons -- not to mention the lives lost by thousands of brave 

 seamen o 



The battle of the Atlantic was the decisive battle of the 

 antisubmarine war. The Germans might win the war if they pro- 

 duced the first atomic bomb They had it won already unless 

 their submarines could be destroyed* 



As they had done during the first World War, the U-boats 

 in 1939 and 1940 again struck savagely at the Allied shipping 

 lanes to Great Britain And the Nazi U-boat of World War II 

 was a far more deadly weapon than its predecessor,, It had 

 greater range, greater speed, greater underwater endurance, a 

 stronger hull, better armament and equipment „ It was a surface 

 raider with the power to submerge and attack from hiding, or to 

 escape beneath the surface if confronted by a stronger foe. 

 Nor could the U-boats be hemmed in, as in the first World War, 

 by mine barrages in the Dover Straits and North Sea c Following 

 the fall of the Netherlands, Belgium, and France, and the occu- 

 pation of Norway, the U-boats could use bases situated along 

 Europe's entire western coast line 



It is a noteworthy tribute to the Allied antisubmarine 

 forces that the record shows that they fought even more effec- 

 tively in the second U-boat war than they had in the first 



