Waterboarding - The Debate, Part 2

The wikipedia article that BowHunter posted contains a definition of waterboarding that seems in line with other authorities on the web. (Yes, I am too lazy to go out and look up the precise legal or procedural definition.) I think a reasonable summary of it would be?

Waterboarding is a technique where a subject is made to believe s/he is drowning, while attempting to hold back from inflicting actual permanent damage and death upon the subject. This technique has been used both as a method of applying psychological pressure for interrogation and as a method of torture to humiliate and break the psyche of prisoners. The technique has been called horrific by most who have been subjected to it, and can lead to brain damage or worse depending on how it is applied and the health of the subject.

This practice is something I hope to never have cause to see or hear about in my daily life.

The other thing we need defined for this discussion to really begin, is "torture" vs "psychological pressure." Dictionary.Com defines torure as "the act of inflicting excruciating pain, as punishment or revenge, as a means of getting a confession or information, or for sheer cruelty." "Psychological Pressure" is harder to define, but the common man's view of it might be "the act of inflicting low-level suffering upon an individual to impel them to an action."

Under these definitions, "psychological pressure" might be a good-cop-bad-cop interrogation of a suspect, or sending a child to stand in the corner to keep him/her from bothering their neighbors. "Torture", on the other hand, might be removing the fingernails of a subject or burning them with hot irons in order to extract a confession.

However, it becomes obvious very quickly that these two definitions are not two different things, but simply positions along a spectrum. Standing in the corner is "pressure", standing in the corner even when one needs to use the bathroom is painful, standing in the corner when one needs to use the bathroom and is hungry and is exhausted is extreme, standing in the corner with all the previous conditions plus an open wound is cruel, standing in the corner for days without sleep or relief is torture, standing in the corner without sleep, food, or relief for long enough is a death sentence.

This leaves us with two real questions that need answering for this discussion:
1. Where along the spectrum does "pressure" become "torture"?
2. In which part of the spectrum does Waterboarding lie?

(I know this is going slow. Stick with me, we're almost to the meat of it.)