The quote that you cite is found about halfway through Chapter 3 of Howard Zinn’s A People’s History of the United States. Most of the rest of the chapter gives his evidence for this, so there is more evidence that we can possibly put in an answer. This is all significant because Zinn is Marxist and Marxism holds that societies are characterized by class conflict. If Zinn is right, then Marxist analysis, and not talk of democracy and rights, can explain colonial American society.
There is a great deal of evidence that, according to Zinn, shows class conflict in the colonies. Some examples include:
- Bacon’s Rebellion was largely caused by poor people angry at the aristocracy.
- There were lots of indentured servants who were treated very badly.
- Abbot Smith, who studied indentured servitude, said that colonial society was “was not democratic and certainly not equalitarian.”
- Carl Bridenbaugh did a study of colonial cities that showed that they had “a clear-cut class system.”
Zinn presents all of this evidence and much more.
His claim is significant because it would mean that conventional wisdom about the colonies (and the Revolution that came out of them) is wrong. We emphasize how the colonies were more democratic and egalitarian than Europe. We emphasize that their rebellion was based on the idea that “all men are created equal.” If Zinn is right, the colonies were the site of Marxist class struggle. This would be a significant finding.