Charts via American Merchant Marine in World War 2
The majority of Allied losses were to U-Boats in the Atlantic. Although Germany was highly successful in the first part of the war, Imperial Japan never pursued an active campaign against shipping in the Pacific.
The overseas transportation of war materials and men by the U.S. Merchant Marine in WWII was key to Allied victory. 1 in 26 mariners serving aboard merchant ships in World WWII died in the line of duty, the greatest percentage of war-related deaths in all U.S. services.
Because of wartime censorship, newspapers reported essentially the same story each week: “Two medium-sized Allied ships sunk in the Atlantic.” In reality, the average for 1942 was 33 Allied ships sunk each week.