When Walter Horita, a second-generation Japanese-Brazilian, staked his first claim in the raw savannah of Brazil's interior, back in 1984, there were no roads, telephones or running water in this stretch of the state of Bahia. Bandits had just murdered his neighbors and taken their land. Undeterred, the 20-year-old lived under a black plastic tarp as he cleared the first 420 acres of armadillos and anacondas for modest crops of soy and rice. Twenty years later Walter Horita's pilot is flying him in his twin-engine Beechcraft over his 74,000-acre estate, tidy homesteads and blindingly white, high quality cotton fields that...