By taking the land occupied by Native Americans.
They started with thirteen, won some in the French Indian war, won some from rev war, bought Louisiana purchase, won from Spanish American war, bought land from Spain, and I think that's it
The United States expanded to include 48 of the 50 states through a series of treaties, purchases, and conflicts from 1783 to 1867. Key events included the Louisiana Purchase, Texas Annexation, the acquisition of Florida, and the outcomes of the Mexican-American War. Ultimately, these expansions were influenced by the ideology of Manifest Destiny, asserting the nation's right to expand its territory across North America.
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