The practice of territorial expansion had been prominent in American thought and action from earliest colonial times. This taking of lands from other nations or from native peoples, was accomplished by both war and treaty. The acquisition of land was made more presentable by justifying it in terms of "Manifest Destiny," - the belief that the westward spread of American control benefited backward people and was ordained by God.
By the 1890s, the western frontier had disappeared, leading some citizens to believe that the period of expansion was concluded. Others, however, saw the completion of the continental empire as a new beginning.
Earlier expansion went beyond the continental boundaries only twice, with the purchase of Alaska and the annexation of Midway, both in 1867. Interest in annexing Cuba was expressed repeatedly prior to 1860, but the contention over the extension of slavery made it impossible for Congress to reach a consensus.
Interest in acquiring Cuba waned following the Civil War, but Americans followed events there closely. A major insurrection, the Ten Years' War (1868-78), pitted the native Cubans against there Spanish overlords. Newspapers reported events on the island and were highly critical of the Spanish.
Attitudes in the United States began to change as European powers became enmeshed in a great quest for overseas empires. Britain, France, the Netherlands, and Japan were major players, and were later joined by Italy and Germany. Emerging imperialist forces thought the U.S. should enter the contest and cited the following reasons:
Wealth. The imperialists argued that the U.S. should avail itself of the natural resources and cheap labor available in many foreign locations.
Pride. In the mind of the imperialists, if the United States wanted to be a great world power, then by jingo, it had to act like one. A leading nation had to have military might and foreign possessions. This swaggering internationalism was voiced by those often referred to as "jingoes," hence the term jingoism.