Some historians strive for complete objectivity, and as such might reject the idea of themes running through their work. Others might argue that any themes found in their work derive from the character of the people or period studied. In the first chapter of A People's History of the United States, Zinn sets forth his approach to history, and it is clear that he would distinguish himself from both positions indicated above. Historians, Zinn argues, always practice "selection, simplification, emphasis," but should be upfront about their purposes in doing so. He uses the analogy of the cartographer, with history being parallel to a map. All maps distort their territories, but they should do so to serve useful, specific, and specified purposes. In a like manner, all historians distort their histories, but should do so to specific ends, and should announce those ends in their work. Therefore, it is wholly appropriate to seek themes in Zinn's history of America. Indeed, tightly interwoven themes make Zinn's work—clumsy though it can be on the stylistic level—highly literary in structure.

Situated Perspectives / Lack of Objectivity

Unsurprisingly, the first theme running through Howard Zinn's A People's History of the United States is that of the situated perspective. Zinn rejects the ideal of objectivity, arguing both that it is not possible and that most texts which claim to provide objective perspectives on reality, especially on American history, do so by leaving out unwanted perspectives and failing to mention specific details that might disrupt their desired representation of the world.

Zinn defines his own situated perspective in Chapter 1: rather than telling the history of the United States from the statist point of view (the history of a state), or from that of a minority ruling class, Zinn's work is the history of the people who make up that nation. As a result, there is a far less emphasis on the standard victories and achievements of the "founding fathers" or the bankers, investors, and explorers whose names repeat throughout America. Instead, Zinn emphasizes the experience of the numerous "minority" groups who together make up the numerical majority: the working class, the poor, Native Americans, slaves, women, and so on.

While Zinn's goals in exploring this perspective are numerous (justice, truth, etc.), Chapter 23 lays out his overarching goals: through the people becoming self-aware, they can create a new and better society. In that way, Zinn's historical map is like that of the early American explorers: it is not just for reference; it is to guide travelers to a new world.

Inclusion and Exclusion

A closely related second theme is that of inclusion and exclusion. To be specific, Zinn argues that the experience of "the people" has been left out of most history books, as well as the dark or shadowy side of history. These two are often linked for Zinn, as the people have often suffered in that darkness, with crimes against them left unmentioned. Zinn therefore moves through American history doing three things: pointing out that which has been excluded from history, filling in those blank spaces in American history, and pointing out who benefited from those crucial details being left out. These range from rounding out the portrait of Christopher Columbus so that it includes his ego as well as his vision, to filling in entire elements of American history that do not fit in the organizing schema found in standard textbooks, such as the widespread labor movements prior to the Civil War. Zinn also makes a point of quoting frequently from a very wide range of sources (laws, speeches, folk songs, interviews, and court testimonies) so that the broadest possible array of American voices is included in his own work.

Manipulated Reality

Most textbooks, Zinn would argue, are complicit in establishing and maintaining a manipulated reality. This reality is manipulated for the benefit of the ruling classes. As such, various crucial elements of American reality that were socially created are treated as natural, or as happening without any one acting to create them. White racism towards African immigrants is one example, as are more generalized attitudes toward African-Americans found throughout American history and culture. Chapter 2 of A People's History of the United States documents how racial prejudice was generated by the conditions of the early colonists, and how blacks and poor whites got along relatively well before entrenched powers worked to convince these poor whites that their common interest lay with the rich white planters rather than with their fellow (black) laborers.

American Hypocrisy

Although he does not excuse competing systems (such as Soviet communism) for their failures, Zinn's focus in this volume is, as the title indicates, on American history. He therefore spends considerable time documenting the hypocrisy with which America has exercised its grand ideals of freedom, democracy, and equality.

Zinn does this in several ways. First, he points out how unsteady are the foundations of American history for such an edifice, by documenting how explorers and colonists, and later, the American government, treated Native Americans. Chapter 1 examines Columbus's treatment of the natives he met, and Chapter 7 examines the Indian Removal Act and associated government military and legal actions. Second, Zinn examines the inconsistency with which America has practiced its ideals within its borders. To be more specific, Zinn hammers home how unequal "equal rights" can be when the poor have no money to act on those rights, and when the rich provide the legislators who pass the laws, the judges who interpret them, and the lawyers who fill the courts. The result, Zinn argues, is a continually rigged game that is continually proclaimed fair for all. Third, Zinn discusses American foreign policy, especially military actions, and demonstrates how often and how deeply these actions are driven by things other than American ideals. In Chapter 12 ("The Empire and the People"), Zinn does this in a simple and damning fashion: he quotes the U.S. State Department's own litany of instances in which armed force was used. This list flatly states that the country uses force to protect "American interests," rather than, as is often claimed, human lives or democratic ideals. Other chapters document an uglier reality still: military force used to shore up American pride or presidential ratings. None of this, Zinn argues, is necessary or inevitable. It is a choice, and one that betrays the ideals America claims to embody.

The Heroism of the Common Man

Zinn's history is not without heroes. However, these heroes are not the generals and inventors who populate many histories. Instead, they are the brave representatives of the people the American ruling class oppressed. As often as he can, Zinn lets these figures speak for themselves. These heroes include members of the revolutionary period Regulators, anonymous rebels who nailed notes to the sheriff of Pittsfield's door in 1780, freed slaves, and striking workers who stood up against armed strikebreakers.

While some of these figures (for example, Sojourner Truth) overlap with traditional heroes from American history, for the most part, they are not the standard heroes. Indeed, given Zinn's perspective on history, they cannot be: these are the people to whom history happens, who try to survive it. Nonetheless, Zinn finds in such figures an endurance, a bravery, and a desire for fair treatment which seems universal. Indeed, the people who Zinn finds heroic are not all found within American borders: they include people like the peasants of Laos who suffered in American attempts to bomb Vietnam. Since the common man, in Zinn's narrative, has not yet reworked society into his own image, the result is somewhat of a paradox. On one hand, the endurance and values practiced at great risk to themselves demonstrate these common men and women are heroes. On the other hand, a litany of so many encounters that are hard to see as anything but defeats makes their heroism seem tragic.