Cross of Iron is a polemic against war, more specifically against war-as-necessity, and it tries to define the role of male virtue in such vicious circumstances. Honor is always defined by circumstance. The huge irony upon which the film turns, however, is that while men may excel in combat, their personal excellence never justifies the context. Here, as in Ride the High Country and The Ballad of Cable Hogue, Peckinpah is openly curious about the stern wisdom that underpins male vanity. (p. 7)
Cross of Iron is no closet drama. Peckinpah avoids the convenient black comedy and intellectual pieties of a [Lina] Wertmüller. The film is punctuated, often unexpectedly, with images of ruined anonymous bodies, humans made meat by the indifferent mechanics of war, a profanation of old values of human dignity. His critics notwithstanding, I don't think Peckinpah is interested in kineticism for its own sake. The violence in this film at every point serves his argument against the moral indifference of war. The polemic is relentless….
Peckinpah also returns to an old obsession: the legacies of violence passed on from father to son…. [He] knows that we are bound to pass on to our children not only our animal instincts but also our monstrous inclination towards atrocity…. Cross of Iron is cogent and powerful, and its unembarrassed rawness persuades where the over-educated black humor of other war films fails. Peckinpah offers no consolation, no phony grace, no pious equivocation. One of his distinctions is that he is an intelligent film artist whose films are seldom polluted by artiness. (p. 8)
W. S. Di Piero, "Sam Peckinpah's 'Cross of Iron'," in Take One (copyright © 1977 by Unicorn Publishing Corp.), Vol. 5, No. 8, March, 1977, pp. 7-8.