Rudyard Kipling's 1899 poem "The White Man's Burden" was addressed to the United States. In it, he is laying out the prevailing feelings of many Europeans towards imperialism and cultural and racial superiority during the late 19th Century.
The previous year, the United States had defeated the Spanish Empire in the Spanish-American War. There was a heated debate in Congress over whether or not the United States should annex the Philippine Islands as part of their war spoils. Kipling, an Englishman born and raised in India, was a staunch imperialist. He felt that the United States (and white people in general) had a duty to "civilize" other peoples whenever they had the chance. In contrast to many European powers, the United States was rather late to the game of acquiring overseas colonies, but now they had the opportunity to join in.
In "The White Man's Burden", Kipling explains the costs of imperialism. He portrays it as full of danger and sacrifice. Nevertheless, he explains that it is the sacred duty and moral obligation of all so-called civilized people to share the blessings of civilization with the world.
Kipling wanted his poem to inspire Americans to join in the imperial ventures of other nations. Specifically, he was urging Americans to support the annexation of the Philippines. It is unclear if the poem directly had this effect but the Senate did ratify the Treaty of Paris, which ceded the Philippines to the US, the day after the poem was published in the New York Sun.