People leave the Islamic Cultural Center of New York under increased police security following the shooting in New Zealand.AP Photo/Mark Lennihan

One of the U.K.’s propaganda films in World War II remixed portions of Leni Riefenstahl’s Triumph of the Will by overdubbing various Nazi leaders’ speeches at the 1934 Reich Party Congress at Nuremberg into English. In this version, Adolf Hitler and his lieutenants confessed to being pitiful and weak. “I grew into a discontented and neurotic child,” the führer said to rallying masses. “My lungs were bad. My mother spoilt me and secured my exemption from military service. Consider my triumphant path to power.”

The author of the words spoken in the satire was Dylan Thomas, the Welsh poet who had a record of jeering at the fascists seeking power in Europe. In a particularly sick perversion of authorial intent, Thomas’s most famous poem, 1951’s “Do Not Go Gentle Into That Good Night,” opens the 74-page manifesto written by one of the alleged murderers of 49 people at two New Zealand mosques on Friday.

The shooter’s document goes on to invoke fascist and white-separatist ideology as the rationale for the murder spree. Certain passages of meme-driven sarcasm appear aimed at amping up political divides and creating confusion. But quoting Thomas’s poetry is not like trollingly praising a black right-wing pundit or a popular and putatively apolitical video-gamer, as the shooter did. The manifesto advocates direct terroristic action by like-minded racists, and Thomas’s refrain “Rage, rage against the dying of the light”—believed to have been written initially about the poet’s ailing father—may just have been straightforwardly repurposed to fit that violent goal.

Two other poems are fully quoted in the manifesto. One is a doctored version of Rudyard Kipling’s “The Beginnings” that replaces the original’s refrain “When the English began to hate” with “When the Saxon began to hate.” The rest of the poem, originally written about the anti-German sentiment that took root in the U.K. during World War I, is untouched. In the context of the manifesto, the verses might as well be about online radicalization: “It was not preached to the crowd. / It was not taught by the state. / No man spoke it aloud / When the Saxon began to hate.”

The manifesto closes with “Invictus,” by the 19th-century English writer William Ernest Henley. With its avowal that “my head is bloody, but unbowed,” it’s among the most commonly cited poems ever, with famous invocations including by Nelson Mandela while he was imprisoned for resisting South African apartheid and Timothy McVeigh before his execution for killing 168 people in the Oklahoma City bombing. Henley wrote the poem in 1875 while recovering from surgery on his leg. It is a straightforward statement of resilience in the face of death, or, as Henley puts it, “the Horror of the shade”: “I thank whatever gods may be / For my unconquerable soul.”

These are not obscure poems, and the varying circumstances around their creation do not tightly align with the New Zealand terrorist’s ideology (though, it’s worth noting, Kipling’s legacy is bound up with racist imperialism). He chose them, plausibly, to undergird his broader message about taking the difficult but necessary action in the face of great odds. He could have turned anywhere in Western culture for other odes to lonely, steely bravery—among the most common story tropes there are—but it may be no coincidence that he drew specifically from the dead-white-male literary canon.

Other mass murderers have invoked different artworks to evoke the same sense of grandiose anti-heroism. James Holmes, who shot up an Aurora, Colorado, movie theater in 2012, found inspiration from the Joker of The Dark Knight. Dylann Roof, the white supremacist who massacred Charleston churchgoers in 2015, quoted two movie characters in his manifesto. One was Edward Norton’s neo-Nazi in American History X: “I see all this stuff going on, and I don’t see anyone doing anything about it. And it pisses me off.” The other was the troubled teen vigilante of the 2011 manga adaptation Himizu: “Even if my life is worth less than a speck of dirt, I want to use it for the good of society.” The killer’s actions, it was widely noted at the time, betrayed these movies’ underlying critiques of violence and hate.

The language of messianic bravery can be adopted by anyone, of course, including those of noble intent. But there’s a particularly nauseating pattern in it being repeatedly invoked by men who kill groups of defenseless people. The Dylan Thomas work actually most relevant to the New Zealand killer’s case is thus not the one quoted in the manifesto, but the Hitler mockery movie. The Übermensch rhetoric that still poisons the world, Thomas suggested back then, is but the costume of pathetic men.

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