Lincoln’s approval of Gen Grant and Sherman’s “scorched earth” treatment of the South makes him culpable for more murder and destruction within the US than any other President in our history.
Well, no, that President would be Jefferson Davis, who chose to launch war against the United States in the belief, accurate as it turned out, that doing so would force Upper South and Border states to choose sides. He also believed, only half correctly, that they would all or most join the CSA.
The story of Sherman's March to the Sea being a Mongol-like continuous massacre serves, like all myths, psychological purposes. That's why myths develop. Oddly, it was universally acknowledged at the time that SC was treated MUCH more harshly than GA, but it's the GA march that gets the publicity.
A similar myth is that held by Irish-Americans of widespread "No Irish Need Apply" notifications in help-wanted ads. Didn't happen. Yet another is the Mormon mythology of systematic attempted extermination by mobocrats in MO and elsewhere.
What all three myths have in common is their taking of actual events and exaggerating them wildly out of all relationship to reality. This then justifies those reveling in the myths in later feelings of victimhood and self-justification.
The "No Irish Need Apply" myth was comprehensively demolished by a scholar who set out to quantify its extent, not disprove it. But what he discovered in his research is that it didn't happen.
For years now I've asked believers in the other two myths (Sherman and Mormon) to post links to research quantifying the extent of the killing and raping (as opposed to property theft and destruction) perpetrated.
Nobody has ever done so. Seems like someone who really believes in these myths would be happy to do the research to document their truth, but this doesn't seem to be the case.
Here's an interesting article by someone who did research the infamous March to the Sea. Not much quantification here, but does cover the reasons the myth developed.
http://people.cohums.ohio-state.edu/grimsley1/myth/myth.htm
Side comment. I've always found it extremely odd that neo-confederates can denounce Sherman's March while at the same time, which most of them do, consider US military policy in WWII of indiscriminate attacks on civilian populations justified.