In 1967, Norman Mailer was present at a march on the Pentagon, organized by the peace movement to protest the war in Vietnam. Writing about himself in the third person, he first gives his own experiences, discussing various aspects of the weekend, from the participants to the larger issues surrounding it. In the second half of the book, he fills in the things he missed, trying to give a more historical perspective, although his imagination is still at work here. Throughout the book he comments not only on the peace movement and the war in Vietnam, but also on some of the other major developments of the time, including the civil rights struggle and the rise of the New Left.

Critics at the time applauded his innovative style of writing, combining a personal and a historical narrative, which “has opened up new possibilities for the literary imagination” (Gilman, 1968). Although some disliked his egotistical tics, overall it was beloved. In the decades since its publication, it has also been widely discussed by historians and critics alike as an important text for the way it details the emergence of the New Left, showing great comprehension of the movement (Miller, 1990). In a review for the New York Times Book Review in 1968, Alfred Kazin describes how it “grew out of the many simultaneous happenings in Washington that weekend, out of the self-confidence which for writers is style, out of his fascination with power in America and his fear of it, out of his American self-dramatizing and his honest fear for his country” (Critical Essays 62). Furthermore, he suggests that the armies were his army, even if he did not “trust his troops, or even his fellow writers on the Left, to be outrageous, strong and imaginative enough” (63). All in all, Armies is an important work as a very personal account of an important moment that was representative of various larger developments.