John Mearsheimer

United States achieved great-power status in about 1898, when it won the Spanish-American War, which gave it control over the fate of Cuba, Guam, the Philippines, and Puerto Rico, and also when it began building a sizable military machine

American foreign policy throughout the nineteenth century had one overarching goal: achieving hegemony in the Western Hemisphere

The United States did not attempt to conquer territory in either Europe or Northeast Asia during the twentieth century because of the difficulty of projecting military forces across the Atlantic and Pacific Oceans against the great powers located in those regions