Zinn describes the results of Columbus's voyages as an unmitigated catastrophe for the natives of the Caribbean (and by extension, all of the Americas.) Columbus and his men were motived primarily by a desire to gain wealth, and they exploited Native Americans to that end. When Columbus arrived in the New World, Zinn says, "the information that Columbus wanted most was: Where is the gold?" Zinn draws heavily on the account of Bartolome de las Casas, who portrayed Columbus and the men that followed him as genocidal murderers, and the end result was that, as Las Casas says, "from 1494 to 1508, over three million people had perished from war, slavery, and the mines." In short, Zinn uses the incident to introduce his narrative, which is intended as a corrective to more traditional accounts that emphasize the exploits of "governors, conquerors, diplomats, leaders."
Source: Howard Zinn, A People's History of the United States (New York: Harper Perennial, 1995)1-9.