The United States emerged from the war relatively unscathed. The American expeditionary force experienced a high casualty rate, including over 100,000 fatalities, but this paled in comparison to the costs incurred by the other great powers. The US was now recognized as a first rate great power. It also transformed from a debtor nation to the world's leading creditor. The US government and US banks - which together had just organized the Federal Reserve system in 1913 - helped to finance the Allied war effort and later the German postwar reparations. The munitions industry also profited from the war - it was the early days of the military-industrial complex. The interests of the "war profiteers" came under heavy scrutiny in the Nye Committee, which helped to influence a disillusioned American public into two decades of isolationism. Although the US never ratified the Versailles Treaty or joined the League of Nations, it continued to play a newfound role in diplomacy. The Washington Naval Treaty and the Kellog-Briand Pact were significant, if ultimately ineffective, achievements in the postwar decade. Anyway, the fact that US power increased dramatically and the US economy benefited from the war while the US suffered relatively far fewer military casualties than other countries and almost no civilian casualties - an outcome that would be repeated again in World War II - makes it the clear winner in my opinion. Every other great power was severely diminished - Germany defeated, Russia plunged into civil war, the Hapsburg and Ottoman empires dissolved completely, Italy and Japan stymied in their ambitions, and Britain and France set on a path of irreversible decline.