Final answer:
Post-WWI, European Allies received substantial financial support from American investors, strengthening the U.S. economy and establishing the dollar's global dominance.
Step-by-step explanation:
Following World War I, American investors, facilitated by Wall Street, which had become the financial capital of the world, provided significant financial support to European Allies, which greatly contributed to the global reach of the U.S. dollar.
As European nations were mired in conflict, these loans were critical in feeding the Allied forces, which in turn brought wealth to the U.S. agricultural sector. The U.S. emerged as an economic powerhouse, leading to a decade of prosperity where technological innovations flourished, and despite the ruinous reparation burdens placed on Germany, the American economy grew.
Moreover, after World War II, these investments and the economic strength of the U.S. played a fundamental role in establishing the international order aimed at securing peace and economic stability worldwide.