The first is that some intelligence and military personal are subject to water boarding as part of their training. From this it is somehow supposed to follow that water boarding is not torture.
This is, obviously enough, a clear non sequiter: the conclusion does not follow from the premise. Suppose that these people were also put on the rack and burned with hot irons as part of their training. It would be absurd to thus conclude that burning people with hot irons is not torture.
In contrast, it would be much more reasonable to conclude that water boarding is torture. After all, these people are presumably exposed to water boarding in order to train them to stand up to enhanced interrogation (that is, torture).
Of course, someone might reply that their point is that water boarding cannot be “that bad.” After all, if it were that bad, then it would not be used in training. The obvious reply is that rather bad things are often used in training. Further, water boarding does seem to be rather bad indeed. True, I rather be water boarded than branded with hot irons, but just because there are worse things it does not follow that it is not bad.
The second is that some people voluntarily endure more suffering and pain than water boarding inflicts, therefore it is not torture. While defining the limits of pain and suffering are critical to understanding torture, this argument does not succeed. The flaw in the reasoning can be shown in the following analogy:
Some people voluntarily suffer severe beatings. For example, professional boxers and football players are subject to attacks that can wound and even kill them. Therefore, tackling somebody or punching them repeatedly in the face should not be considered assault and battery. However, this is clearly absurd. Just imagine, if you will, someone trying that defense in court: “Your honor, I plead not guilty. Yes, I punched the person in the face over and over. But boxers take that kind of abuse all the time. So clearly, what I did cannot be assault.”