The years following the Civil War were the years of great economic expansion in United States history. With increased industrial production, the demand for resources grew rapidly and as the lands under US control could not meet this demand, the only option was to expand the territorial area. In 1867, the United States purchased Alaska from Russia and the same year it annexed the Midway Islands. Until the 1890s, expansion was limited to the west and did not extend beyond the country's borders. But the 1890s, the period between 1893 and 1903, was a turning point in United States history, marked by America's expansion outside its continent for the first time. Although policymakers justified imperial expansion through the doctrine of manifest destiny, other causes, particularly the Depression of 1893, strategic military acquisitions to improve U.S. security, international competition and the need to control more of the world in order to become the world power, actually encouraged the United States to expand beyond its borders. This changed America's traditional foreign policy from isolationist to interventionist, which dragged America into various international conflicts at the risk of its own security. After 1865, facilitated by the development and expansion of railroads, American industries grew rapidly and pushed their production beyond domestic demand. These advances attracted immigrants from around the world, rapidly increasing the population of the United States. This increase in population, wealth, and industrial production required more resources, and with America already expanding westward, the only option was to explore areas outside of national borders.... . middle of paper...... With this responsibility comes a threat, a threat against one's own people. Works Cited • Graebner, Norman A. Foundations of American Foreign Policy. Wilmington, Scholarly Resources Inc., 1985 • McKinley, William. “President McKinley on the American Empire.” Voices of Freedom: A Documentary History, edited by Eric Foner—3rd ed. New York: WW Norton & Company, 2011• Jayne, Madison M., An American Time Capsule: Three Centuries of Broadsides and Other Printed Ephemera, “Imperialism Defined and Demonstrated,” September 8, 1900. http://memory.loc . gov/cgibin/ampage?collId=rbpe&fileName=rbpe08/rbpe085/0850170c/rbpe0850170c.db&recNum=0&itemLink=D?rbpebib:1:./temp/~ammem_Id14::@@@mdb=manz,mharendt,rbpebib,cwband,cwnyh s ,gmd,mreynoldsbib,mtaft,cwar,fsaall,mfdipbib,mff,scsmbib,mal,mcc,ncpm,pan,afcpearl,lhbprbib,afc911bib,papr,runyon,detr,mgw,nfor,sgp,sgproto,ww2map&linkText=0