Expansion and empire building were concerns for American leaders as soon as national independence became a reality, and issues of growth and hegemony grew more important into the first half of the nineteenth century. The United States expanded rapidly and significantly across the continent. By purchase and conquest, national leaders gained lands in the Northwest Territory, the Louisiana Territory, Florida, the Pacific Northwest, and the Southwest, while attempting to bring Canada and Caribbean areas such as Cuba under American sway, too, though without success. While it would be difficult to observe a consistent anti-imperial ideology in this period, there was criticism of and actions directed against territorial acquisition, Indian removal, and manifest destiny. Often, such opposition served the interests of political expediency or power—as with northeasterners or Federalists voting against the Louisiana Purchase or the War of 1812. Critics, however, also objected on moral grounds or, presaging an argument that would become especially powerful in the Cold War era, the excessive, or imperial, use of executive power in foreign affairs.
The United States was born out of a war of national liberation against the world's greatest empire at the time, and thus tended to deny its imperial ambitions or to describe them benignly. Benjamin Franklin and Thomas Paine, for instance, popularized the idea that America could establish a "benevolent" empire while they condemned the British for policies of the "extermination of mankind," rather than just conquest, in their colonies. Indeed, the founding generation was conflicted despite the apparent consensus on expansion. While there was a compelling political will to develop an "empire of liberty"—to use President Thomas Jefferson's words—there was also a continuing republican ideal that was distrustful of empire and its needs for standing armies, heavy taxes, large bureaucracies, and centralized decision making.
At the same time, there were strong isolationist tendencies among the ruling class. Not anti-imperialist per se, these isolationists did warn against American "entanglements" in other lands. Indeed, in his farewell address President George Washington, like John Quincy Adams an ardent expansionist using anti-imperial rhetoric, suggested that "harmony, liberal intercourse with all nations are recommended by policy, humanity, and interest. But even our commercial policy should hold an equal and impartial hand, neither seeking nor granting exclusive favors or preferences; consulting the natural course of things; diffusing and diversifying by gentle means the streams of commerce, but forcing nothing." Rooted in the fresh memories of the war against British imperialism, ambivalent views on state power, and an attachment to republican values, this isolationism had real meaning to many Americans and was practiced in their political affairs.
Thus, when President Jefferson purchased the Louisiana Territory from France, effectively doubling the size of the United States, critics attacked his actions as unconstitutional and imperial. Federalists, ironically using arguments that had been advanced against them by their political foes during the debate over the Constitution, contended that the purchase of trans-Mississippi lands was unnecessary and dangerous, for emigration into the new areas would "be attended with all the injuries of a too widely dispersed population, but by adding to the great weight of the western part of our territory, must hasten the dismemberment of a large portion of our country, or a dissolution of the Government." Such disputes notwithstanding, the Senate approved the acquisition of Louisiana, although the Constitution did not explicitly grant executive power for territorial expansion; subsequently, it authorized commercial restrictions and military engagements against Britain and accelerated a national program of Indian removal.
While the growth of a continental empire in the early nineteenth century may have been inexorable, it did not always proceed smoothly, for diverse voices were raised in protest against American expansion during the major episodes of territorial aggrandizement in the period. Representative John Randolph of Virginia was wary of imperial designs. "What! Shall this great mammoth of the American forest leave his native element," he asked, "and plunge into the water in a mad contest with the shark?" Federalists stung by a swing in political influence and sectional growth toward the south and west opposed the War of 1812, with some beginning to develop a critique of expansion and even to consider the secession of New England states at the Hartford Convention (1814–1815). The defeat of Indians in the Creek War and the Battle of Tippecanoe, followed by General Andrew Jackson's invasion and eventual seizure of Florida in 1818, however, made anti-imperial critiques more difficult. Still, many questioned what they saw as the contradiction of maintaining republican virtues within a growing empire with an expanding military and a willingness to use force in the pursuit of national interests. Although the enthusiasm for new lands might have seemed frenzied, many Americans were concerned about unrestrained growth and especially lamented the destruction of Indian society.
After the War of 1812, the federal and state governments intensified their efforts to oust Native Americans from their lands, with General (later President) Andrew Jackson the leading figure in the era, attacking the Seminole in Florida and the Cherokee and other tribes in the southeast with particular ferocity. By the 1820s and 1830s, there was significant division over Indian removal and continental expansion. In 1831, when Georgia, relying on a Supreme Court decision that Indians were neither U.S. citizens nor a foreign nation, and with the support of President Jackson, expelled the Cherokee from their indigenous lands despite their treaty rights to it, evangelical Christians organized mass protests and condemned removal, comparing it to a crime against humanity.
Questions of morality and constitutionality—not unlike those raised in the late twentieth-century debates over the Vietnam War or intervention in Central America—were common throughout the Cherokee crisis as critics scored the national and state governments for violating the Constitution by rejecting Indian treaties. Writing under the pseudonym William Penn, Jeremiah Evarts, the chief administrator of the American Board of Commissions for Foreign Missions, an interdenominational missionary organization, exposed and denounced the U.S. attack on Indian sovereignty on the bases of morality, history, and the Constitution. Throughout the colonial period and under the Articles of Confederation and the Constitution, Evarts pointed out, various authorities had, by treaty, guaranteed the territorial integrity of Indian lands; the Cherokee and other tribes, which had never surrendered such title, still held "a perfect right to the continued and undisturbed possession of these lands." The Indians, he added, did not hold lands in Georgia or any other state, but were sovereign, "separate communities, or nations." Removal was, in the minds of Evarts and many other critics of aggressive expansion, "an instance of gross and cruel oppression." While such views held great currency—the vote in Congress to approve Jackson's removal program was quite close in fact—they were not those of the majority, and Indians embarked on their infamous "Trail of Tears" while many millions of acres of Native American lands in the southeast were soon opened to agricultural exploitation.
The appropriation of Indian territory occurred in a period of great expansion, because Americans believed it was their "manifest destiny" to acquire new lands. Advocates of this ideology believed that the United States had a providential right and obligation to assume control over less-developed areas in the name of republicanism, Christianity, and white supremacy. Expansionists even had a quasi-legal justification for building a continental empire, the Monroe Doctrine. Crafted by Secretary of State John Quincy Adams and announced by President James Monroe in 1823, the doctrine was a statement of Pan-American influence in which the United States warned European powers to keep their "hands off" newly independent states in Latin America. Unspoken but just as compelling was the idea that the United States had a natural hegemony over the region and would expand control over all the Americas in time.
Again, however, John Quincy Adams seemed to be of two minds, refusing diplomatic or material aid to revolutionaries in South America and Greece because it would jeopardize the national interest by entangling the United States in the affairs of other countries and delivering his "America goes not abroad" oration, but also penning the Monroe Doctrine as part of his vision of a continental empire. To some critics, Adams's ideas were in fact endangering the national interest, with one member of Congress describing the Monroe Doctrine as "assuming an unwarrantable power; violating the spirit of the Constitution; assuming grounds and an attitude toward European Powers, calculated to involve us in the strife which there existed, and in which we had no interest; and indirectly leading to war, which Congress alone had the right to declare."
In addition to such continuing constitutional questions and insular concerns, critiques of expansion and empire invariably became intertwined in the intensifying slavery controversy, and almost always included attacks on the southern political and planter aristocracy, which had designs not only on the continental west but also on areas in the Caribbean, such as Nicaragua and Cuba, in which to extend their slave system. By the mid-1840s, these conflicting forces of southern expansionism and antislavery sentiment would lead to a national antiwar-cum-anti-imperialist movement.
The effective cause of the acute division of the era was the American war against Mexico, begun in 1846 but the culmination of a generation of U.S. attempts to absorb Texas into the Union. While there were strong sentiments north and south for bringing Texas and other southwest lands into the United States, the inevitable expansion of slave states gave rise to often fierce condemnations of expansion. John Quincy Adams, now an independent representative in Congress and a leader of antislavery, anti-imperialist political forces, feared that the annexation of Texas would turn the United States into a "conquering and warlike nation." Ultimately, "aggrandizement will be its passion and its policy. A military government, a large army, a costly navy, distant colonies, and associate islands in every sea will follow in rapid succession." Senator Thomas Corwin of Ohio echoed Adams's views, describing President James Polk as a "monarch" and his cabinet as a "court," and considering justifications for the war as a "feculent mass of misrepresentation." The "desire to augment our territory," Corwin lamented, "has depraved our moral sense." Ralph Waldo Emerson, noted essayist and earlier advocate of taking Texas, now predicted that the United States would gobble up new lands "as the man swallows arsenic, which brings him down in turn," and his fellow Transcendentalist Henry David Thoreau refused to pay poll taxes, received a jail sentence, and wrote his famous essay "Civil Disobedience" in protest of the Mexican War.
Such critiques held great popular and political appeal in the 1840s as pacifists, abolitionists, religious leaders, and literary figures pressed an anti-imperial agenda while 90 percent of Whig Party members in Congress voted against the war. Following the acquisition of Texas, California, and other Mexican lands in the southwest, anti-imperialists may have been on the defensive, but they were not quiescent. When, in the 1840s and 1850s, southern planters began to create and subsidize filibusters, military adventurers who tried to invade and secure Latin American lands for new plantations and slavery, abolitionist anti-imperialists protested vigorously. Whig politicians and an emerging political movement of Free Soilers, opponents of the extension of slavery into new territories, especially attacked the deeds of soldiers of fortune such as Narcisco López, who sought to invade Cuba in 1849, 1850, and 1851, and William Walker, the "grey-eyed man of destiny," who briefly conquered and ruled Nicaragua in the late 1850s. Indeed, the firm opposition of the Whigs and Free Soilers, as well as abolitionists and some evangelical elements, effectively thwarted southern dreams of a Caribbean empire in the antebellum period. They could not, however, suppress the intensifying sectional crisis, and civil war had become unavoidable by 1860 when Abraham Lincoln, who as a Whig representative opposed the Mexican War, was elected president. Within a half-decade, the conflict between the Union and the breakaway states of the Confederacy was over, and the United States was about to embark on its greatest imperial efforts yet, but not without protest and opposition at all points along the way.