The expansion of influence and territory off the continent became an important corollary to westward expansion. The U.S. government sought to keep European countries out of the Western Hemisphere and applied the principles of manifest destiny to the rest of the hemisphere. As secretary of state for President James Monroe, John Quincy Adams held the responsibility for the satisfactory resolution of ongoing border disputes between the United States, England, Spain, and Russia. Adams’s view of American foreign policy was put into clearest practice in the Monroe Doctrine, which he had great influence in crafting.
Increasingly aggressive incursions from Russians in the Northwest, ongoing border disputes with the British in Canada, the remote possibility of Spanish reconquest of South America, and British abolitionism in the Caribbean all triggered an American response. In a speech before the U.S. House of Representatives on July 4, 1821, Secretary of State Adams acknowledged the American need for a robust foreign policy that simultaneously protected and encouraged the nation’s growing and increasingly dynamic economy.
America . . . in the lapse of nearly half a century, without a single exception, respected the independence of other nations while asserting and maintaining her own. . . . She is the well-wisher to the freedom and independence of all. . . . She well knows that by once enlisting under other banners than her own, were they even the banners of foreign independence, she would involve herself beyond the power of extrication, in all the wars of interest and intrigue, of individual avarice, envy, and ambition, which assume the colors and usurp the standard of freedom. The fundamental maxims of her policy would insensibly change from liberty to force. The frontlet on her brows would no longer beam with the ineffable splendor of freedom and independence; but in its stead would soon be substituted an imperial diadem, flashing in false and tarnished lustre the murky radiance of dominion and power. She might become the dictatress of the world; she would be no longer the ruler of her own spirit. . . . Her glory is not dominion, but liberty. Her march is the march of the mind. She has a spear and a shield: but the motto upon her shield is, Freedom, Independence, Peace. This has been her Declaration: this has been, as far as her necessary intercourse with the rest of mankind would permit, her practice.37
Adams’s great fear was not territorial loss. He had no doubt that Russian and British interests in North America could be arrested. Adams held no reason to antagonize the Russians with grand pronouncements, nor was he generally called upon to do so. He enjoyed a good relationship with the Russian ambassador and stewarded through Congress most-favored trade status for the Russians in 1824. Rather, Adams worried gravely about the ability of the United States to compete commercially with the British in Latin America and the Caribbean. This concern deepened with the valid concern that America’s chief Latin American trading partner, Cuba, dangled perilously close to outstretched British claws. Cabinet debates surrounding establishment of the Monroe Doctrine and geopolitical events in the Caribbean focused attention on that part of the world as key to the future defense of U.S. military and commercial interests, the main threat to those interests being the British. Expansion of economic opportunity and protection from foreign pressures became the overriding goals of U.S. foreign policy.38 But despite the philosophical confidence present in the Monroe administration’s decree, the reality of limited military power kept the Monroe Doctrine as an aspirational assertion.
Bitter disagreements over the expansion of slavery into the new lands won from Mexico began even before the war ended. Many northern businessmen and southern slave owners supported the idea of expanding slavery into the Caribbean as a useful alternative to continental expansion, since slavery already existed in these areas. Some were critical of these attempts, seeing them as evidence of a growing slave-power conspiracy. Many others supported attempts at expansion, like those previously seen in eastern Florida, even if these attempts were not exactly legal. Filibustering, as it was called, involved privately financed schemes directed at capturing and occupying foreign territory without the approval of the U.S. government.
Filibustering took greatest hold in the imagination of Americans as they looked toward Cuba. Fears of racialized revolution in Cuba (as in Haiti and Florida before it) as well as the presence of an aggressive British abolitionist influence in the Caribbean energized the movement to annex Cuba and encouraged filibustering as expedient alternatives to lethargic official negotiations. Despite filibustering’s seemingly chaotic planning and destabilizing repercussions, those intellectually and economically guiding the effort imagined a willing and receptive Cuban population and expected an agreeable American business class. In Cuba, manifest destiny for the first time sought territory off the continent and hoped to put a unique spin on the story of success in Mexico. Yet the annexation of Cuba, despite great popularity and some military attempts led by Narciso López, a Cuban dissident, never succeeded.39
Other filibustering expeditions were launched elsewhere, including two by William Walker, a former American soldier. Walker seized portions of the Baja peninsula in Mexico and then later took power and established a slaving regime in Nicaragua. Eventually Walker was executed in Honduras.40 These missions violated the laws of the United States, but wealthy Americans financed various filibusters, and less-wealthy adventurers were all too happy to sign up. Filibustering enjoyed its brief popularity into the late 1850s, at which point slavery and concerns over secession came to the fore. By the opening of the Civil War, most saw these attempts as simply territorial theft.