Howard Zinn is as responsible for poisoning the minds of American students with anti-American rubbish as anyone who ever lived. His distorted "history" is one of the reasons more people know about the Japanese internment during World War II than the Normandy invasion, more about injustices against native Americans than the liberation of Eastern Europe, more about slavery than the US Constitution, more about the failings of the founding fathers than their great accomplishments.
A high school history teacher I know once said that it's easier to teach negative history. "The kids get more engaged than just memorizing names and dates." If so, then it's like a drug. You might feel good but it's not necessarily good for you.
Even Zinn admitted his view of "history" was not meant to be factual. But liberals are content to see the world through individual feelings more than facts and so Zinn's garbage has been used widely by the left leaning education establishment to indoctrinate generations of young people. I'm not one for banning books but his certainly should not be allowed in US schools.
The results are devastating as a corrupt political establishment tramples on the US Constitution and nobody seems to notice or care.