I've mentioned this before, during Nixon's Watergate Scandal, the secretary of defense requested the Joint Chiefs report to him if they received any 'unusual orders' from Tricky Dicky.
So there is precedent (IANMTU) for the upper echelons of the US government being aware 'unlawful' orders could emanate from the Oval Office and that there being some thought into dealing with that possibility.
As for an 'intramural' use of nukes, I note that at one time the US government was aware at least one other nuclear power had contingency plans for that sort of thing.
[shudder]
So there is precedent (IANMTU) for the upper echelons of the US government being aware 'unlawful' orders could emanate from the Oval Office and that there being some thought into dealing with that possibility.
As for an 'intramural' use of nukes, I note that at one time the US government was aware at least one other nuclear power had contingency plans for that sort of thing.
[shudder]
The granting of a pardon is an imputation of guilt, and the acceptance a confession of it.