More than 50 percent of the supplies sent to Europe and Africa from the United States were shipped from ports in the Gulf of Mexico and passed through the Caribbean. One year after the Pearl Harbor attack, the United States Caribbean Defense Command reached a total of 119,000 personnel, half of them stationed in Panama to protect the canal from an anticipated Japanese attack. Meanwhile, the German Kriegsmarine inflicted massive damage on shipping in the Caribbean in 1942. By the end of that year, U-boats operating in the Caribbean had sunk 336 ships, at least half of which were oil tankers.