The late nineteenth-century and early twentieth-century United States expansionism was a continuation of past United States expansionism.
The Louisiana Purchase and the Mississippi River proved to be important trade routes for the United States along with the New Orleans's harbors for resources and raw materials in early expansion years. Along with California being annexed, the trade with Asia opened along with the Pacific. The United States during early expansion was thinking towards expanding its land to gain more trade with nations and more natural resources for its expanding populati…