A rationale for peremptory norms?
Concerning this paragraph from the article, especially the last sentence,
Some peremptory norms define criminal offences which are considered to be enforceable against not only states, but individuals as well. This has been increasingly accepted since the Nuremberg Trials (the first enforcement in world history of international norms upon individuals) and now might be considered uncontroversial. However, the language of peremptory norms was not used in connection with these trials - rather the basis of criminalisation and punishment of Nazi atrocities was that civilisation could not tolerate their being ignored, because it could not survive their being repeated.
The notion of that which civilization will not tolerate because it cannot survive its repetition, seems the very cogens of jus cogens: how can Nuremberg assert a criterion so relevant to jus cogens, and not be said to have used the language of peremptory norms?   This seems offered as an enduring standard, not a one-off. What evidence do we have of how the legal novelty suggested in the paragraph was perceived or discussed by either the participants or later analysts? 

On a separate point, I don't have a date for the language quoted in the paragraph, wouldn't it be towards the end of Nuremberg's 1945-1949. I wonder whether it somehow echos in "The Constitution is not a suicide pact," which was from a (later?) 1949 dissent.