The history of modern Mexico and particularly that of the Revolution and its aftermath is a constant theme in Fuentes's novels. That Revolution failed to change significantly the lives of most of Mexico's citizens. This fact seems to be the reason behind Fuentes's Marxist outlook on history. His sense of outrage caused him to accept and continue to cling to ideas that, for at time at least, the rest of the world has rejected. He too rejected the Moscow version of Communism, but his own individualistic Marxism has not been carefully defined. It is probably more of an emotional response to seemingly hopeless social problems than one capable of producing a well reasoned blueprint for social renewal. He distrusts both capitalism and totalitarian Marxism.

Fuentes believes that emptiness and a lack of fulfillment characterize the people at all levels in the Mexican capital. Most of these people are either unaware of this, or sense it only occasionally. Related to this emptiness is the theme of betrayal, the Cain motif as the critic Gyurko has pointed out (see reference in biographical entry on Fuentes). Federico Robles, Fuentes's representative member of the nouveau riche class, betrays the principles of the revolution and the Indian people, his own origins.

Violence and death occur frequently in this novel, and Fuentes suggests that they lie close to the surface of life in the city and the rest of Mexico. Ixca Cienfuegos, who serves as Fuentes's ubiquitous spokesman, insists that it makes little sense to commit suicide in Mexico "because of the very good chance that at any moment you may be killed by someone else." Juan Morales, a taxi driver, is killed "at the beginning of the novel, and Manuel Zamacona is murdered toward the end gratuitously by a man who did not like the way the poet looked at him. Zamacona, most of whose efforts are directed to establishing the Mexican identity, becomes a victim to the violence he recognizes as all too frequent a component of the national character.

Culture Clash
One of the most powerful themes of Where the Air Is Clear is the sharp division between the social strata of 1950s Mexico City, along the fault lines of income and class, as well as race—with the indigenous Indians placed in the lowest rank, like the prostitute Gladys. Fuentes illustrates the conflict between the old and the new reigning members of the Mexican elite in several scenes, such as the dinner at the impoverished de Ovando household where the social climber Norma Robles meets the bitter aristocratic matriarch Lorenza de Ovando. The event is set up by Lorenza's cousin Pimpinela, an ambitious beauty struggling to retain her family's status and save them from starvation. Pimpinela is an example of the fully adapted social member, who willingly trades ‘‘class for cash’’ both in her marriage and at the salon parties. She asks the opportunist wife Norma Robles to use her husband's influence and get her company shares; as soon as she mentions dinner at her aunt's, Norma cannot ‘‘keep her eyes from shining.’’ In turn, Pimpinela tells Lorenza that ‘‘an upstart, obnoxious, vulgar’’ married to ‘‘a savage from God knows what jungle'' is coming to dinner, and it is necessary for the aunt to welcome her so that her grandson can get a job at the bank.

The old aristocrat's determination to show the nouveau riche her place fails, as "Norma, radiant, wrapped in mink and playing carelessly with her pearls, visibly affirmed the sense of security in this new world, of freedom and belonging, which had used to be [de Ovandos'] own feeling.’’ After the dinner, Lorenza and Norma return to their social circles, competing to point out the flaws of the other: one criticizes the lack of grace and presumptuous airs of the "daughter of some sheepherder'' who dared to take her place at the top of the hierarchy, and the other ridicules the aristocrat's refusal to accept well-deserved defeat. In the meantime, both fragments of the upper class live in denial: Lorenza awaits another revolution to restore her class because her grandson, Benjamin, has no skill beyond his aristocratic European grooming; while Norma tells her fashionable friends that her mother is actually an old servant, and her husband Federico hides his Indian heritage under expensive suits and white facial powder.

Fuentes also shows the sharp contrast between the peak and the bottom of Mexico City's social food chain in one of the book's first chapters, in which the narrative cuts back and forth from the lavish parties of the nouveau riches to the filthy slums inhabited by the poor. The lonely morning of the aging prostitute Gladys, after a night of work in a smoky nightclub, stands in stark opposition to the after-party morning of the jet set: some of its members are sleeping, and others preparing for another day of successful transactions (Norma is tanning and pampering herself, and Pimpinela is on the way to collect her shares at the bank). Every once in a while, the narrative jumps from the memories of its wealthy characters to descriptions of the usually nameless members of the poor or working classes, whose everyday activities appear as incredulously different and more burdensome than those of the recently arisen bourgeoisie.

The Supernatural
Part of the elusive identity of Fuentes's 1950s Mexico lies in the suppressed ancient past and the country's pre-Hispanic Indian heritage. The characters of Ixca Cienfuegos and his mother Teodula Moctezuma embody this past, its religion and spirituality, and bring a mysterious and supernatural element into the potpourri of the modern Mexican selfhood. Teodula at first appears to be praying to the Catholic Virgin Mary, but her words of worship, offering of her heart, and the skirt made of serpents show that her goddess is actually Coatlicue—the Aztec earth deity, who daily gives birth to the sun in the morning and swallows it in death in the evening. In Aztec representation, Coatlicue wears a necklace of human skulls and hands; she is a womb and a tomb at once, giving birth to death. Her son, the god of war, kills all of her other children as soon as he is born. Likewise, Teodula has lost all of her children, except Ixca—whom she sends out to find her a blood sacrifice that would redeem the suffering of her people. Deeply engaged in a death cult, Teodula performs rituals over the skeletons of her husband and children. She also calmly speaks of her own death and accepts it as a part the natural life cycle.

Ixca's monologues, at the beginning and the end of the novel, are full of invocations of ancient spirits as the only true and authentic powers over his land. His personality is mystical and undefined throughout the novel: there are speculations about his life and social position, but nobody knows for sure who he is or what he does. A symbolic embodiment of an ancient god of war, Ixca attempts to perform his duty on several occasions: for example, he tries to persuade Rodrigo to kill himself, and pushes Norma overboard into tempestuous waves. When Norma dies in a house fire witnessed by Teodula, the old woman tells her son that the sacrifice is completed and he withdraws from social life.

Ixca's identity as a deadly entity appears in allusions: Rosa's son, frightened by Ixca's invitation to take him to eat, bites the man's hand and makes it bleed. The next time the boy is mentioned, he is dead and Rosa is preparing to bury him. When Ixca tastes his own ‘‘acrid [and] metallic’’ blood from the bitten hand, ‘‘his head swam with that taste; blood whirled in his ears like two breaths, united by an hour of terror.’’ The boy might have been mysteriously poisoned by Ixca's blood, but the unspoken connection between events remains.

The character of Hortensia, Federico Robles' blind mistress of Indian origins, is another possible mythical embodiment: her connection with the world, especially with her lover, has some supernatural qualities. As opposed to the mysterious forces of Ixca and Teodula, Hortensia represents the nurturing, healing power of ancient Mexico; Federico goes to her to free himself from the pain of his everyday life at the social peak, and returns to her after he loses everything to start a happy and fulfilling life of redemption on a farm. Hortensia feels a certain affinity with Ixca, which further alludes to her possible mythical identity; she senses that they both ‘‘come from far away,’’ can ‘‘understand without words,’’ and have ‘‘faces that frighten us and carry us to the limits of passions, good and evil’’ and that would cause fear in others, ‘‘who would destroy us if we would show our true faces.'' Also, she speaks of her relationship with Federico as a union outside his social domain, the reality beyond ‘‘what life has made him,’’ and declares that ‘‘the world which at last will be Federico's and [hers] is right here’’ and will make itself known once Federico finds his ‘‘true face.’’ Like Ixca, Hortensia appears to believe in a true Mexico underneath the ruling modern one, waiting to emerge after the destruction of the cultural constructs; once that destruction happens in her lover's life, Hortensia embraces him and offers him a new, clean beginning.