When they brought it, they were given copper tokens to hang around their necks. Indians found without a copper token had their hands cut off and bled to death. The Indians had been given an impossible task. The only gold around was bits of dust garnered from the streams. So they fled, were hunted down with dogs, and were killed." Zinn details similar atrocities committed by Cortes against the Aztecs. He was also a Spaniard whose expeditions were financed predicated "and blessed by the deputies of God" and predicated on the hope of repayment in gold from the New World:

"Cortes then began his march of death from town to town, using deception, turning Aztec against Aztec, killing with the kind of deliberateness that accompanies a strategy-to paralyze the will of the population by a sudden frightful deed. And so, in Cholulu, he invited the headmen of the Cholula nation to the square. And when they came, with thousands of unarmed retainers, Cortes's small army of Spaniards, posted around the square with cannon, armed with crossbows, mounted on horses, massacred them, down to the last man. Then they looted the city and moved...

When their cavalcade of murder was over they were in Mexico City, Montezuma was dead, and the Aztec civilization, shattered, was in the hands of the Spaniards."
Conclusion

In principle, Zinn's main thesis is that the historical record published and popularized for centuries in Western societies is a very subjective and slanted account. It glorifies the end result of European explorers while substantially mischaracterizes the truth of the brutality they inflicted on native peoples. Likewise, it completely ignores the manner in which the European explorers hailed as heroes to this day actually violated the most fundamental moral and religious values by abusing, enslaving, and brutally murdering millions of innocent human beings, wiping out entire societies that had been living peacefully in the Americas for thousands of years before being invaded by the European explorers we regard as heroes today. Zinn suggests that this positive spin on history to glorify accomplishments and downplay (or ignore entirely) the tremendous injustices they involved is a ubiquitous feature on contemporary historical literature.