Also another bit of history, when the US won the war, they found out and found the leader of the facility and the people responsible. They did not prosecute them for war crimes, instead they gave them a deal that if they handed over there information they have collected on their human experiments they would go free, this is because most US scientists where do eager to gave data like this cause in the US they weren't allowed to do these experiments.
Later on in 1951 - 1953 the leader of the facility was on the front lines with the US in the Korean conflict, that was when they started to use chemical weapons against the Koreans as well. US is not as innocent as you think.
jt