3.1 American Imperialism and World War I
Learning Target 15. Analyze the circumstances which enabled the United States to emerge as a world power in the early 1900s.

The 1890 U.S. Census led many Americans to conclude that there was no longer a frontier line in the West. With the closing of the western frontier, Americans developed positive attitudes toward foreign expansion.
The primary factors that led to American imperial expansion were global competition for markets and prestige, an expanded navy, and a sense of cultural superiority. The growth of industrialization demanded more natural resources (raw materials) and new markets for products. An expanded naval fleet and overseas ports were also believed to be essential to economic prosperity and security of the nation. The belief in “manifest destiny,” first used to defend westward expansion, was now used to argue that the U.S. had a right and duty to extend its influence and civilization in the Western Hemisphere and across the Pacific.
The United States engaged in a series of overseas actions which contributed to its increasing status as a global power. In 1898, the U.S. annexed Hawaii. American sugar planters wanted to annex Hawaii to eliminate tariffs. Control of Hawaii was also important strategically to serve as a mid-Pacific naval base.
U.S. support for Cuban independence and protection of U.S. commerce and trade led to war with Spain in 1898. The Spanish-American War ended Spain’s empire in the Western Hemisphere. U.S. victory in the war produced a peace treaty that required the Spanish to give up claims on Cuba, and to hand over control of Guam, Puerto Rico, and the Philippines to the U.S.
In 1917, the U.S. entered World War I on the side of the Allies. With its entry into war, the United States mobilized a large army and navy to help the Allies achieve victory. After the war, European countries were forced to concentrate their resources on rebuilding their countries. However, the United States enjoyed a brief period of economic prosperity and was able to assert authority as a world power.
The primary factors that led to American imperial expansion were global competition for markets and prestige, an expanded navy, and a sense of cultural superiority. The growth of industrialization demanded more natural resources (raw materials) and new markets for products. An expanded naval fleet and overseas ports were also believed to be essential to economic prosperity and security of the nation. The belief in “manifest destiny,” first used to defend westward expansion, was now used to argue that the U.S. had a right and duty to extend its influence and civilization in the Western Hemisphere and across the Pacific.
The United States engaged in a series of overseas actions which contributed to its increasing status as a global power. In 1898, the U.S. annexed Hawaii. American sugar planters wanted to annex Hawaii to eliminate tariffs. Control of Hawaii was also important strategically to serve as a mid-Pacific naval base.
U.S. support for Cuban independence and protection of U.S. commerce and trade led to war with Spain in 1898. The Spanish-American War ended Spain’s empire in the Western Hemisphere. U.S. victory in the war produced a peace treaty that required the Spanish to give up claims on Cuba, and to hand over control of Guam, Puerto Rico, and the Philippines to the U.S.
In 1917, the U.S. entered World War I on the side of the Allies. With its entry into war, the United States mobilized a large army and navy to help the Allies achieve victory. After the war, European countries were forced to concentrate their resources on rebuilding their countries. However, the United States enjoyed a brief period of economic prosperity and was able to assert authority as a world power.