Running an empire demanded more than a treaty. The US labored for decades before and after the Spanish-American War to lay the groundwork and administrative systems that supported its new borders. This section explores how America officially annexed Puerto Rico, the Philippines, and Hawaii.
Beginning in the fifteenth century, Puerto Rico was a stronghold of Spain's Caribbean empire. With the outbreak of the Spanish-American War, the US quickly set its sights on San Juan. American troops invaded and occupied Puerto Rico in July 1898 and met little resistance. Puerto Ricans welcomed the US as a liberator. They interpreted American collaboration as a chance for economic reform and eventual freedom. By October, Spain surrendered Puerto Rico to American troops, yet with peace came new tension. Puerto Ricans lobbied for independence. Politicians in Washington, DC questioned where exactly Puerto Rico—and the other new territories—stood in relation to mainland politics.
Debate came to a head with a series of Supreme Court rulings known as the "insular cases." These determined that the Constitutional rights allotted to states and citizens did not apply to Puerto Rico or its people, even though the territory was subject to taxes, legislation, and other obligations dictated by Congress. According to the Supreme Court, Puerto Rico would be "foreign in a domestic sense."