Who did Churchill call the "American Carnot" in WWII?

Winston Churchill called U.S. Army Chief of Staff George C. Marshall the “American Carnot” during World War II.

The comparison referred to Lazare Carnot, the French military organizer who helped mobilize and direct France’s armies during the Revolutionary Wars. Churchill saw a similar role in Marshall, who reorganized and expanded the U.S. Army as the Second World War approached and then coordinated its enormous wartime growth.

Marshall became Army Chief of Staff in 1939, shortly before the United States entered the war. Under his leadership, the Army expanded from a relatively small peacetime force into a global military organization. He was central to officer selection, training, logistics, strategic planning, and the deployment of American forces alongside the Allies.

The nickname does not mean Marshall was primarily a battlefield commander. His greatest wartime contribution was administrative and strategic: building the force that could fight effectively across multiple theaters. Churchill also praised him as an “organizer of victory,” a description that captures why the Carnot comparison mattered.