From An Army at Dawn: The War in North Africa, 1942-1943, Volume One of the Liberation Trilogy, by Rick Atkinson (Henry Holt, 2002), Kindle Loc. 7950ff:
“The battle,” Rommel famously observed, “is fought and decided by the quartermasters before the shooting begins.” The shooting had begun months before in northwest Africa, but now the quartermasters truly came into their own. The prodigies of American industrial muscle and organizational acumen began to tell. In Oran, engineers built an assembly plant near the port and taught local workers in English, French, and Spanish how to put together a jeep from a box of parts in nine minutes. That plant turned out more than 20,000 vehicles. Another new factory nearby assembled 1,200 railcars, which were among 4,500 cars and 250 locomotives ultimately added to North African rolling stock.
In late January, Eisenhower had pleaded with Washington for more trucks. Less than three weeks later, a special convoy of twenty ships sailed from Norfolk, New York, and Baltimore with 5,000 two-and-a-half-ton trucks, 2,000 cargo trailers, 400 dump trucks, 80 fighter planes, and, for ballast, 12,000 tons of coal, 16,000 tons of flour, 9,000 tons of sugar, 1,000 tons of soap, and 4,000 submachine guns, all of which arrived in Africa on March 6. “It was,” an Army account noted with justifiable pride, “a brilliant performance.”
In World War I, more than half of all supplies for American forces were obtained abroad, including nearly all artillery and airplanes. In this war, almost everything would be shipped from the United States, including immense tonnages sent to the Russians, British, French, and other allies. The demands of modern combat were unprecedented. Although a latter-day infantry division was half the size of its Great War predecessor, it typically used more than twice as much ammunition—111 tons on an average fighting day. In Africa, total supply requirements amounted to thirteen tons per soldier each month.
Can do. From late February to late March, 130 ships sailed from the United States for Africa with 84,000 soldiers, 24,000 vehicles, and a million tons of cargo. Although the U.S. II Corps lost more armor at Kasserine than the Germans had massed at the beginning of the battle, those losses were replaced immediately. Other matériel appeared just as fast, including 500 miles of extra communications wire shipped to the front from Algiers less than a day after it was requested. When Patton requested—no, demanded—new shoes for his entire corps, 80,000 pairs arrived almost overnight. So much ammunition arrived in Tunisia that it was stacked in pyramids and thatched with branches to simulate an Arab village.
The Americans’ “genius lay in creating resources rather than in using them economically,” a British study observed astutely.