The alternative to illiberal nationalism and “very lefty” identity politics that Lepore proposes is a version of civic patriotism that she distinguishes from liberal nationalism and calls simply “liberalism.” Although Lepore is on the center-left, like conservatives such as the late Harry Jaffa and so-called West Coast Straussians she asserts that American identity consists of little more than a shared belief in the egalitarian ideals of the founding fathers. Lepore paraphrases the Declaration of Independence: “All people are equal and endowed from birth with inalienable rights and entitled to equal treatment, guaranteed by a nation of laws.”

As for liberal nationalism, Lepore argues that it is an oxymoron. She says that the historian Tony Judt was “probably right” that liberal nationalism is “essentially nothing more than a thought experiment,” and that if “nation-states didn’t already exist, they wouldn’t really be a great thing to invent.” According to Lepore, “Nation-states are people with a common past, often a mythical one, who live under the rule of a government in the form of a state.” The contrast she draws between liberal nationalism and nonnational civic patriotism is stark: “Patriotism is animated by love, nationalism by hatred.” The subtitle of her book — “The Case for the Nation” — should have been “The Case Against the Nation.”

The United States has never been a nation-state at all, Lepore claims, but that rare “hen’s tooth” in world politics, a “state-nation” (a term originally devised to describe multinational post-colonial states in Africa and the Middle East and elsewhere). Her attempt to disentangle good American patriotism from bad American nationalism, however, tangles American history in knots. Isolationism is nationalist — “American nationalism in the first decades of the 20th century also took the form of economic nationalism and advocacy of isolationism.” But interventionism can be nationalist, too: America’s entry into World War I “only stoked nationalism.” And Franklin Roosevelt cannot easily be disentangled: He is a patriotic Dr. Jekyll when he leads the United States into World War II but a nationalist Mr. Hyde when he signs the order for the internment of Japanese and Japanese-Americans.

Lepore acknowledges that a liberal nationalist alternative to illiberal nationalism and illiberal identitarianism has long existed: She points to such figures as Abraham Lincoln, the Roosevelts and the post-1945 “Cold War liberals.” But she notes with regret: “In American history, liberals have failed, time and again, to defeat illiberalism except by making appeals to national aims and ends.”

To build up her preferred alternative to liberal nationalism, she denigrates the liberal nationalists of the civil rights era: “Cold War liberalism, for all of its celebration of American civic ideals, turned only belatedly and inadequately to the question of civil rights.” As evidence for this accusation, she cites the fact that the historian Arthur M. Schlesinger Jr. wrote speeches in the 1950s for Adlai Stevenson, who, as a presidential candidate, urged “at most, a gradualist approach” to desegregation. But Schlesinger was a co-founder, with Eleanor Roosevelt and John Kenneth Galbraith, among others, of Americans for Democratic Action, as well as its national chairman in 1953-1954. Its members supported President Truman in 1948 in integrating the armed forces and promoting civil rights measures, which led the racist Dixiecrats to break away from the party, nearly costing the Democrats that year’s presidential election. Belated and inadequate?