Yes, it was ruled invalid. That doesn't make it invalid. That ruling was pure evil. The trials were a sham, existing only so that a democracy could participate in dishing out victor's justice. It's revenge, pure and simple, coldly ignoring the pressure that people were under.
This is also why I think Snowden did the right thing: he may have "betrayed his country" by helping inform the public about what is going on, but it was his moral responsibility to do so. If he had kept his mouth shut, he would have become an accomplice to the crime.
I've already been in a situation where I could choose between serious jail time and refusing orders I did not agree with so I'm pretty sure which side I would come down on.
So, with all respect mr. Anonymous Coward you haven't a clue what you're talking about.
Principles come at a price, that's for sure.
I can see why you have a problem with this worldview.
Unless refusing orders would mean somebody else jails you, no you haven't been in that situation. The deal is that you follow orders and maybe get jailed/executed after losing a war, or you disobey orders and definitely get jailed/executed right away.
In addition to Hans Fritzsche, Franz von Papen, and Hjalmar Schacht in Nuremberg, over 1,000 Japanese defendants were acquitted of war crimes in postwar trials.
Sure, Göring was sentenced to death by hanging, but he conspired to steal Jewish property after Kristallnacht and there was clear evidence he was complicit in the attempted extermination of the Hungarian Jews. So, yeah, didn't go well for him.
Contrast that though with the higher ranking Dönitz, effectively head of state. His defense actually worked fairly well, and he received a lighter sentence.
On charges that he sunk neutral vessels, his defense countered that the US had done the same, so he received no additional jail time.
On charges that he waged unrestricted warfare against British merchants, he received a "not guilty" as his defense argued that the merchants had all supported the war effort.
He claimed that he didn't know anything about the policy in the camps, since he was only involved with naval matters. He was the final head of a genocidal state, and received just a 10 year sentence, lighter than some murderers get.
EDIT: I think you're right that there are mitigating factors when people are acting under orders (especially given the behavior in question falls well short of genocide), but I don't think the Nuremberg trials were a sham trial.