Picking up on this comment thread, I came across this fascinating article on the reasoning behind the use of what has come to be called waterboarding in the Christian tradition. The author makes a strong case for seeing waterboarding as a perverted inversion of baptism.
In the Inquisition, the practice was not drowning as such, but the threat of drowning, and the symbolic threat of baptism. The tortura del agua or toca entailed forcing the victim to ingest water poured into a cloth stuffed into the mouth in order to give the impression of drowning. Because of the wide symbolic meaning of “water” in the Christian and Jewish traditions (creation, the great flood, the parting of the Red Sea in the Exodus and drowning of the Egyptians (!), Christ’s walking on the water, and, centrally for Christians, baptism as a symbolic death that gives life), the practice takes on profound religious significance. Torture has many forms, but torture by water as it arose in the Roman Catholic and Protestant reformations seemingly drew some of its power and inspiration from theological convictions about repentance and salvation. It was, we must now surely say, a horrific inversion of the best spirit of Christian faith and symbolism. Is it the purpose of the United State nowadays to seek the conversion, repentance, and purity of supposed terrorists and thus to take on the trappings of a religious rite? The question is so buried behind public discourse that its full import is hardly recognized.