The decades on both sides of the turn of the twentieth century were the golden age of American imperialism, if such a thing can exist. The military supported a sugar planter coup in Hawaii, which was ultimately annexed. The Spanish-American war, which was initially fought to protect human rights in Cuba, became a raw exercise of imperialism; Puerto Rico and Guam became American possessions, our country claimed a right to intervene in the politics of nominally independent Cuba, and we fought a bloody guerrilla war to subdue rebels in the Philippines. TR engineered and supported a coup in what subsequently became Panama to expedite the construction of the canal. Woodrow Wilson shelled Veracruz for specious reasons and sent the US Army over the border after Pancho Villa. And those were only the famous episodes.
These were not mostly private-sector attempts at ethnic cleansing, as with the Native Americans; these events were primarily initiated by the US government for geopolitical and economic reasons. They were an embarrassment by the 1930s. A new era was about to begin.