These Truths by Jill Lepore is a one-volume political history of the United States, from 1492 to 2016. Lepore’s guiding question is whether the United States has realized, or can realize, “these truths” held self-evident in the Declaration of Independence: equality for all, natural rights, and consent of the governed. Her accounting of the nation’s history seeks to address these questions.

In 1492, Europeans arrived in North America and rapidly began to oppress and exploit the people indigenous to the continent, whom they also killed in large numbers. Though the first colonists were Spanish, the English began to found colonies in the early seventeenth century. Shortly thereafter, European merchants brought the first enslaved Africans to North America. The legacy of stolen land and stolen lives shaped the country that became known as the United States. In the eighteenth century, the English colonists grew dissatisfied with being ruled and taxed by an English king and Parliament they had no say in. They declared their independence from Britain and created a brand-new nation, founded on the ideals of equality for all mankind, natural rights, and government of the people by the people. Yet from the beginning, the nation was contaminated by the abuses that had made its founding possible. Slavery shaped the Constitution on a fundamental level, determining how states would be represented in the legislature by creating a system, designed to protect slaveowners, that endures today: a Senate with two representatives from each state and a House with proportional representation.

As the new nation developed, the elements of government that we recognize today slowly fell into a place: political parties, presidential primaries, Supreme Court decisions. Many of the systems that developed arose in response to slavery, either to protect it or as part of attempts to abolish it. The fight for civil rights, women’s rights included, became the history of the nation. Though many struggled to keep it together, the question of slavery ultimately tore the country in two, creating a brutal and bloody civil war. Though the abolitionist side won and slavery technically became illegal, many remained committed to the oppression and exploitation of Black people.

A struggle for economic justice characterized the late nineteenth and early twentieth centuries, as populists and then Progressives worked to help the poor and relieve inequality. Progressivism, the belief that government should be used to help poor people, was realized in the New Deal, President Franklin Roosevelt’s project to lift the nation out of the Great Depression. But liberalism and conservatism in their modern forms were both shaped by world politics. After fighting the two world wars to “make the world safe for democracy,” the United States found itself locked in a cold war with Communist Russia. Conservatives found their identity as anticommunists, ultimately unifying their party around the social issues that eventually became its center by tying those issues to the threat of socialism. Liberals responded to the needs of the poor and, eventually, to the protests of Black people demanding their civil rights. In the 1960s, effective civil rights legislation finally passed.

The parties were not particularly polarized in the 1960s, but political strategists worked to make them increasingly more so over the decades that followed. Using abortion and gun control as “wedge issues” to divide the electorate, they made Americans fear that their fundamental rights were being threatened. Conservatives undercut the authority of institutions like the media and science, while liberals turned their attention away from the working class. The fragmentation of media made the polarization worse, as people began to only follow the news sources they already agreed with and...