The outrage over a video allegedly showing U.S. marines urinating on dead Taliban fighters provided Americans with a disturbing reminder that war can reduce men to revenge-seeking brutality that defies human norms.

It's nothing new: the desecration of enemy soldiers during the Civil War,  Japanese soldiers during World War II, North Vietnamese fighters during the Vietnam War and Iraqis and Afghans in the most recent conflicts is well documented.

Such acts have religious implications. "Virtually all religions have reverence for the dead. Different religions, especially the monotheistic faiths, don't accept any desecration of their own dead, or the enemy's dead," said Carl Raschke, a religious studies professor at the University of Denver.

For example, Muslims believe that after death their bodies will slowly disintegrate, except the tailbone, which on the day of resurrection will regenerate into the complete human being. For that reason, most Muslims reject cremation because it destroys the tailbone, making resurrection impossible. Still others believe that the resurrected body will appear as it did at the moment of death, and for that reason they fear and condemn desecration of the dead.

Within Islam, desecration of enemy war dead was forbidden by the Prophet Muhammad himself. When warriors mutilated dead Muslim soldiers during one battle, Muhammad commanded his soldiers not to do the same. At another battle, the opposing army offered to pay Muslims for the return of one of its famed warriors. Muhammad responded, "I do not sell dead bodies. You can take away the corpse of your fallen comrade."

"It's considered a sin and a crime," said Imam Muzammil Siddiqi, chairman of the Fiqh Council of North America, which interprets Islamic law.

Respect for the dead has been a core teaching within Christianity, in part because of belief in bodily resurrection. Christian churches have softened on cremation in recent years as the practice becomes more popular.

"The bodies of the dead must be treated with respect and charity, in faith and hope of the Resurrection," the catechism of the Catholic Church teaches. "The burial of the dead is a corporal act of mercy; it honors the children of God, who are temples of the Holy Spirit."

Hindus believe that the soul, or Atman, leaves the body at the moment of death, starting a journey to the next life. The condition of the body has no impact upon the soul's journey or its ultimate destiny, but a dead person has to be properly cremated under specific funeral rites if the departed soul is to have a peaceful journey to the next life.

"It is believed that if the dead body is not properly cremated, the journey of that soul is disrupted or becomes difficult," said Dileep Thatte, founder of the Seven Stars of Hinduism, a nonprofit group in Chicago that educates people about Hinduism.  

"There is nothing whatsoever in the Vedic literature that promotes desecration of war dead," explained Bhupender Gupta, a Hindu priest in Cary, North Carolina. "These are humans, brethren, who performed their duties as commanded."

Zulu warriors were famous for disemboweling their foes, but not out of revenge or brutality. Rather, Zulus believed that a bloating decomposing body signified spirits trying to escape the corpse. Zulus believed that if they did not release the spirits of their victims,  they would suffer the same fate.

Within Judaism, mutilating a dead body—even through an autopsy—is also strictly forbidden.

Nancy Sherman, a philosophy professor at Georgetown University who specializes in war ethics, ventured a guess as to why people worry about human remains. In a CNN.com commentary about the return of dead soldiers' bodies to their loved ones, she wrote that "we want something of that for our dead, so that we can mark an honorable passage from this world."

The various military branches follow similar guidelines on how to handle enemy dead. "Desecration is not tolerated in any way, shape or form," said Lt. Col. Joe Kloppel, a U.S. Marine Corps spokesman. While there is no way to ensure that marines read or practice the prohibition against desecration, Kloppel said, "it's made very clear to marines at various levels what's right and what's wrong." —RNS