Answer:
The closing of the frontier in the late 19th century had an impact on U.S. imperialism in the 1890s. It made Americans look beyond their borders for new opportunities and territories to expand into. It also created a demand for new markets abroad. Lastly, it led to the desire for strategic naval bases to protect American interests overseas.
The Spanish-American War began in 1898 for several reasons. It started because Cuba was fighting for independence from Spain and the United States supported them. The sinking of the USS Maine also increased tensions between the US and Spain. Lastly, sensationalized media coverage called yellow journalism played a role in shaping public opinion and stirring up war sentiment.
The outcomes of the Treaty of Paris of 1898 were that Spain gave up control of Puerto Rico, Guam, and the Philippines to the United States. Cuba gained independence, although the US still had influence over the island. The United States also gained control over the Philippines, leading to a period of US colonization there.
Overall, the Spanish-American War and the Treaty of Paris marked a turning point in US foreign policy and expansionism, solidifying America's emergence as a global power.
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