That, and the fact that it's TORTURE, ....
Is the use of a knife on a body torture? Maybe when it is a sadist carving you up to cause pain, but what about when it is a surgeon removing a tumor? The US has routinely waterboarded members of its military. Are you claiming that it tortured them? That isn't what Eric Holder said when he was Attorney General. He specifically said that it wasn't torture. Coercive? yes. Torture? No, not as it was done.
...the sort of thing we prosecuted people for in the past as a war crime.
A common claim, usually made in reference to the Japanese, but it isn't true. What the Japanese did was different than what the US did to a total of 3 (three) members of al Qaida ending in 2002.
It's also completely useless for gathering information, because all you get is garbage - someone will tell you whatever they think you want to hear to make it stop, even making shit up.
That seems to rely on some big and potentially false assumptions, and doesn't appear to be necessarily true.
Waterboarding Has Its Benefits
U.S. and Pakistani authorities captured KSM on March 1, 2003 in Rawalpindi, Pakistan. KSM stayed mum for months, often answering questions with Koranic chants. Interrogators eventually waterboarded him ... KSM’s revelations helped authorities identify and incarcerate at least six major terrorists:
Jesse Ventura put it rather well when he said something on the lines of "Give me Dick Cheney strapped to a folding table and a pitcher of water, and in 5 minutes I'll get him to confess to the Manson Family murders."
Jesse Ventura doesn't seem to understand the point of interrogation even if he does understand coercion. It is probably a bad idea to rely upon his views on this.