I have set out to make an original response to the enduring question critics have engaged with in the decades since Lionel Trilling called Frost terrifying. Clarifying in the first section some of the key terms of trauma theory, and describing its potential relevance to Frost, I seek in the second section to offer readings of five poems that show how changing focalizations create a sense of an implied author who has been traumatized. But the question is suggested: what was Frost traumatized by? So, in the third section I offer biographical, theoretical, and textual evidence that he was traumatized by a special kind of alienation as it it understood by Marxist theory—to wit, the death of a sense of species-being. Frost, I argue, is terrifying because he is so persuasively in denial, as a poet and a cultural figure, about the wounding effects on him of capitalist culture.