If Nietzsche’s image reached its nadir during the Second World War, when Hitler presented Mussolini with a bound edition of his works and the historian Crane Brinton wrote a book asserting he would have been “a good Nazi,” a resurrection was soon to come. The German émigré and Princeton professor Walter Kaufmann almost single-handedly revived his standing with his many translations and forceful reminder that Nietzsche hated anti-Semites and German nationalists as well as woolly-headed romantics. Kaufmann’s Nietzsche was a late flower of the Enlightenment, a tough-minded rationalist with the courage to face the Darwinian revelation that there is no purpose to nature or to our existence. The true task of the overman was to overcome himself, not others, and to do so by sculpturing his impulses and thoughts and inheritances into a willed unity that could be called “style.”

But did Kaufmann and others who treasured Nietzsche’s intransigent individualism as a defense against the threats of totalitarianism and mass culture lose sight of his actual writings? As Ratner-Rosenhagen shows, a later generation of American interpreters, influenced by Michel Foucault and Jacques Derrida, esteemed Nietzsche not as the guarantor of the individual but as its dismantler. “The ‘doer’ is merely a fiction added to the deed,” Nietzsche wrote in “On the Genealogy of Morals,” and the implication was clear: If God was dead, so too were equally fictitious entities like the self. There was no objective truth, only the truth-effects engendered by the workings of power and the instabilities of language. Even as this poststructuralist Nietzsche occupied the university in the 1980s, it bred a counterreaction from conservative intellectuals. In “The Closing of the American Mind,” Allan Bloom decried the “Nietzscheanization of the Left,” by which he meant the rise of a disabling relativism that supposed any belief was as good as any other. For Bloom and other students of Leo Strauss, however, Nietzsche was not just the disease, he was also the diagnostician and possibly the cure. More brilliantly than anyone, Nietzsche understood the peril of modern nihilism and the need to cultivate robust souls who would strive to achieve excellence without authoritative religious belief.

“American Nietzsche” is a sober work of intellectual history, but as Nietzsche insisted, all scholarship reflects the temperament of its creator, and it’s clear that Ratner-Rosenhagen finds neither the poststructuralist nor the conservative Nietzsche at all satisfying. At the end of her consistently insightful book, she turns to Harold Bloom and the philosopher Stanley Cavell, who emphasized Nietzsche’s affinities with the man he himself regarded as “the most fertile author” of his century — Ralph Waldo Emerson. Indeed, one can show that Emerson anticipated many of Nietzsche’s most famous utterances. There is a direct line from Emerson’s “oversoul” to the “overman.” Several decades before Nietzsche wrote, “What does not kill me makes me stronger,” Emerson wrote, “In general, every evil to which we do not succumb, is a benefactor.” More profoundly, Emerson foreshadowed Nietzsche’s concern with the ubiquity of flux and power, and the value of overcoming the past. “Life only avails,” Emerson once wrote, “not the having lived. Power ceases in the instant of repose; it resides in the moment of transitions from a past to a new state.”

Ratner-Rosenhagen concludes that Cavell, Bloom and the pragmatist philosopher Richard Rorty constructed “an American Nietzsche” by drawing upon “philosophical interpretations which understood that in a world without foundations, our views of truth, language and the self are not mirrors of reality but useful fictions to explore new avenues of discovery, new sources of wonder.” Stressing Nietzsche’s Emersonian and pragmatist heirs, Ratner-Rosenhagen inevitably neglects some of his other pertinences. She doesn’t take into full account how Nietzsche thought his beloved Emerson was “too much infatuated with life” or how he doubted most people could ever discover anything at all. Nor does she say much about his broader presence in the culture. In 1933, the Hays Office forced the producers of the Barbara Stanwyck film “Baby Face” to remove “The Will to Power” from the hands of a German-American cobbler whose paeans to self-fulfillment inspire the Stanwyck character to become a prostitute. Nietzsche’s more bombastic utterances would later enter popular culture without hindrance. In every generation Nietzsche finds admirers who blur his message with that of Aleister Crowley, the Nietzsche-reading occultist who wrote, “Do what thou wilt shall be the whole of the law.”

If Nietzsche was terrible, was he also beneficial? In a 1985 book “Nietzsche: Life as Literature,” the Princeton philosopher Alexander Nehamas argued that Nietzsche’s perspectivism does not imply that all beliefs are equally valid but that “one’s beliefs are not, and need not be, true for everyone.” On this reading, to fully accept a set of beliefs is to accept the values and way of life that are bound up with it, and since there is no single way of life that is right for everyone, there may be no set of beliefs that is fit for everyone. At its best, American individualism is not about the aggrandizement of the self or the acquiescent assumption that everybody simply has a right to think what they want. Rather, it stresses that our convictions are our own, and should be held as seriously as any other possessions. Or, as Nietzsche imagined philosophers would one day say, “ ‘My judgment is my judgment’: no one else is easily entitled to it.”