Southern Expansionism.

The Kansas-Nebraska controversy not only initiated a political realignment in the North but wrecked any chance to fulfill the primary ambition of the Pierce administration and many of its Southern supporters, the acquisition of Cuba. After initially looking benignly on "filibustering" expeditions through which Americans sought to foment revolution in Cuba, the beleaguered Pierce adopted a new policy in May 1854 threatening to prosecute violations of American neutrality laws. The administration then authorized a futile effort to buy the island, but when the minister to Spain, Pierre Soule, and two other American diplomats issued the "Ostend Manifesto" declaring that the United States would be "justified in wresting it from Spain," the president forced Soule to resign. Meanwhile, other expeditions held out to Southerners the tantalizing prospect of a slave-based empire extending through Central America. William Walker, a sometime physician, lawyer, and journalist...