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If we never discovered that Jared Lee Loughner honed his murderous outlook while sitting alone in his bedroom, reading Nietzsche and thinking about nihilism, that would have been real news. Instead of real news, though, we've gotten a dreary iteration of a cultural cliché. The New York Times and other media are saying the addled and alienated young man arrested for trying to assassinate Gabrielle Giffords, and for the murders of 9-year-old Christina Taylor Green and five other people, took himself to be a Nietzschean. Of course he did.
I suppose we could start plucking out incendiary quotations from Nietzsche's works and assess how much blame to lay on his head for Loughner's alleged crimes and the crimes of other young men with similar philosophical interests, but such a project would tend toward philistinism or obscurity. Better, I think, to leave aside the indictment and treat the nexus of Nietzsche and troubled young manhood as Nietzsche himself would have—that is, anthropologically.
The attraction of Nietzsche to socially maladjusted young men is obvious, but it isn't exactly simple. It is built from several interlocking pieces. Nietzsche mocks convention and propriety (and mocks difficult writers you'd prefer not to bother with anyway). He's funny and (deceptively) easy to read, especially compared to his antecedents in German philosophy, who are also his flabby and lumbering targets: Schopenhauer, Hegel, and, especially, Kant. If your social world fails to appreciate your singularity and tells you that you're a loser, reading Nietzsche can steel you in your secret conviction that, no, I'm a genius, or at least very special, and everyone else is the loser. Like you, Nietzsche was misunderstood in his day, ignored or derided by other scholars. Like you, Nietzsche seems to find everything around him lame, either stodgy and moralistic or sick with democratic vulgarity. Nietzsche seems to believe in aristocracy, which is taboo these days, which might be why no one recognizes you as the higher sort of guy you suspect yourself to be. And crucially, if you're a horny and poetic young man whose dream girl is ever present before your eyes but just out of reach, Nietzsche frames his project of resistance and overcoming as not just romantic but erotic.
If you're a thoughtful and unhappy young man, in other words, why wouldn't you want to read someone who seems to reflect both your alienation and your uncontainable desire back to you as masculine bravery and strength? Indeed, there's something in every book you're likely to pick up—some enticement of form or content or both—that addresses your horniness/alienation and flatters you in the pretense that, though you have no formal training and are actually kind of a crappy and distracted reader, you are doing philosophy.
In The Birth of Tragedy, Nietzsche's first work, it's the celebration of anarchic and sexually with-it Dionysus over boring Apollo, who's like the Greek god of algebra or something. In Zarathustra, it's the beckoning first-person narration, a crazy novel or memoir kind of thing, a heroic story of Zarathustra "going under," gathering spiritual strength in hermetic solitude that reminds you of your own bedroom, and then "rising" to "shine" upon a people who don't even understand or deserve him. In The Genealogy of Morals it's Nietzsche examining the real history of that Bible stuff your lame pastor barks at you in church (which you understand as saying two main things: no sex, no touching yourself) and proving that morality originates not in God but in the will to power—ancient priests seizing power over ancient masters by guilt-tripping them about the suffering of slaves. (Christianity is just "slave morality." So much for that dilemma.) In Ecce Homo it's those excellent chapter headings ("Why I Am So Clever," "Why I Write Such Good Books"). And in Beyond Good and Evil it is, well, the awesome title of the book itself, and that hilarious opening line ("Supposing truth is a woman—what then?"), and that first chapter where he mocks all those philosophers you don't have to read anymore, now that Nietzsche has told you how lame they are.
And, also in Beyond Good and Evil, it's the aphorisms—a section entitled "Epigrams and Interludes" comprising over a hundred one- and two-sentence masterworks of moral paradox and counterintuition, calculated outrage and elegant eye-poking. Nietzsche is aphoristic even when he's being systematic, and when he's being aphoristic, his writing is simply unmatched in its beauty and mayhem, its uncanny mix of compression and infinite suggestion. And for a young guy who's intellectually hungry but doesn't much enjoy reading, finding this section of philosophy-bits in the middle of this famous book is like a homecoming. You don't even have to know what these epigrams mean to enjoy them. You just feel manly and brave in entertaining them at all, not flinching but laughing when Nietzsche says: "One is best punished for ones virtues." (You even get to work out some of your girl-troubles by lingering over Nietzsche's several jabs at women.)
Of course, Nietzsche scholars will tell you not to run too far with these little wisecracks. You need to understand them in the context of his larger body of work, in which he often circles back to themes, again and again, revising and even contradicting his earlier writings. You have to understand the aphorisms as part of a vast poetic project of self-creation or becoming in which nothing is truly settled. Nietzsche himself predicted he would be misread, acquire misguided disciples, and so he has.