The part of the border that divides the Dominican Republic from Haiti on the southern coast of the island of Hispaniola is seldom reached by outsiders, and the conflicts that transcend the metal gate between the towns of Pedernales, on the Dominican side, and Anse-à-Pitre, in Haiti, seem reminiscent of the children’s stories of Dr. Seuss that warn against infantile stubbornness and teach the morals of cooperation.