I despair at your reading skills sometimes...
It has nothing to do with 'not being responsible' ultimately. It has to do with that he did not, cannot, have personally planned it all. For the simple reason that there is not enough time in the day to plan such futile details (as they must have been for them).
Look at that last disaster in Afghanistan where that soldier shot 16 innocent civilians because he went potty (rightly so, the military should not have sent him there so many times and in such a short space of time). Can you hold Mr Obama personally accountable for that? I hope you are going to say 'no', but I fear the simplistic answer will be 'yes', though.
Granted they can court martial if they find it necessary, however, was he, if
he had disapproved of the Einsatzgruppen
going to put them all in prison? Really?
I repeat it again, for the umpteenth time, he is responsible like a minister is responsible for what happens in his ministery or like a president is responsible for what his civilians in their official functions do in cases of violence. he is not personally accountable.