So I came across something very interesting and quite germane to this discussion during some reading today. Turley keeps referencing Nuremberg as a precedent for the "just following orders" defense not working. However, this defense has apparently been rejected since at least 1626, when Parliament impeached the Duke of Buckingham basically for dereliction of duty. The Duke responded by saying he was doing to King's bidding and Parliament rejected those claims, saying:
As it turns out, the code of justice that says that one does not have to obey unlawful orders is centuries old. Informative historical caveat and context.The Laws of England teach us, That Kings cannot command ill or unlawful things, whenever they speak, though by their Letters Patents, or their Seals. If the things be evil, Letters Patents are void, and whatsoever ill event succeeds, the execution of such commands must ever answer for them. (sic)