Wasn’t it Sherman who advised the Kaiser in the Franco Prussian war? His advice was, let it be known if the populace resists with violence you will burn down their houses. (He did mention to let the people leave first.). If there is no resistance leave them alone.
I have no doubt he felt guilt. But as war criminals go he wouldn’t make the list. Too many were much better at it.
Uh ... no.
First I've heard of it anyway.
Sherman was still a professional military man after the war, and was Commanding General of the Army from 1869 to 1883. He wouldn’t have been able to officially advise a foreign head of state of anything under those circumstances.
Sherman was commanding general of the U.S. Army during the Franco-Prussian war. Phillip Sheridan was there as an observer but he didn't advise the Kaiser. Bismark was doing that.