Since the time of the Constitution, racism frequently has been a part of the mix of factors that shaped diplomacy. Although there were other forces involved, such as the unbridled national enthusiasm for "pole to pole" territorial expansion, race became an articulated element of the expansionist policies associated with "manifest destiny." The term first appeared in 1845, and suggested that the Almighty in his ultimate wisdom had "manifestly destined" the procreative and vigorous Americans to extend their ennobling institutions of republican governance. The result was seen by some as way to spread superior democratic ways of life, but to others, focused on race, it provided a way to replace uncivilized and backward populations with those of purer blood.
President James K. Polk (1845–1849) translated "manifest destiny" into a plan of action, and the result was the annexation of Texas, purchase of the Oregon Territory, and a war with Mexico that resulted in the northern one-third of that nation being ceded to the victorious United States. Settling the western land acquired during the Polk administration, and the intervening Civil War, dampened further interest in foreign policy initiatives until the 1890s. By the turn of the century there were new ideas that had gained currency and influenced incorporating race into the making of foreign policy.
The British biologist Charles Darwin had introduced his theory of evolution in On the Origin of Species (1859), and by the turn of the century his views had been widely popularized in America. Evolutionary theory suggested that in the biological world, higher life-forms evolved through a process of "natural selection," popularized as "survival of the fittest" in the struggle for existence. Such a hypothesis was easily applied by some to sociological theorizing, even in the realm of international affairs. Since there was a ruthless struggle for existence within the biological sphere that resulted in survival of the fittest, or "best," some concluded that a similar struggle among nations or races might produce similar results. Ruthless international competition might well be justified in the name of "progress." Popular writers and clergymen believed that in the future, Anglo-Saxons, particularly Americans, would dominate in the world.
America's foreign policy initiatives were the result of a variety of forces, and one such force was racism. Before, during, and after his presidency (1901–1909), Theodore Roosevelt expounded upon the Social Darwinist interpretations of "natural selection," "survival of the fittest," the supremacy of Anglo-Saxons, and the "white man's burden" to uplift and civilize backward peoples. It is sometimes difficult to separate the racism from other factors that motivated conduct. Yet as America began to move into the world at large around the turn of the twentieth century, attitudes of racial superiority were observable. One example is provided by the American presence in the Philippines following the settlement of the war with Spain in 1898.
When it became clear to the Filipino nationalists that the United States was intent on occupying the islands rather than providing for their independence, a four-year war ensued. The historian Brian McAllister Linn, in The Philippine War, 1899–1902, warns that it is incorrect to ascribe racism to all the vicious behavior of American troops against the Filipinos. However, even with Linn's cautionary note that such behavior has been typical of combat soldiers for hundreds of years, the evidence demonstrates that part of the reason for the poor treatment of Filipinos was racial hostility.
The pacification and occupation of Central America and the islands of the Caribbean during the early decades of the twentieth century also reflect America's attitude of racial superiority. The occupation of Haiti from 1915 to 1934, for instance, resulted from a mixture of morality and strategic concerns, along with racism. Reflecting the racial attitudes of American policy and the occupation troops, Haitians were involuntarily placed in labor gangs, beaten and terrorized, and treated as prisoners. Marines killed two thousand "workers" in 1919, following an insurrection. Enforced segregation was imposed, and Americans favored the mulattos over the darker skinned Haitians. Secretary of State Robert Lansing, who had deployed marines in Haiti, wrote that the "African race" had an "inherent tendency to revert to savagery and to cast aside the shackles of civilization which are irksome to their physical nature. Of course there are many exceptions to this racial weakness, but it is true of the mass as we know from experience in [Haiti]."