You contradict yourself -- for obvious reasons.
Sherman himself articulated the policy, per your quote, of Schrecklichkeit -- which is what Heinrich Himmler called it later.
Please notice that this is not a standardized, gratuitous and rhetorical comparison of some person to the Nazis. Here, the comparison is germane, it's supported by the quotation and by evidence from the field, and it goes to the heart of Sherman's intentions.
Sherman did not intend to shorten the war by depriving the South of the ability to fight. He sought to shorten it the way the Nazis intended to shorten their war with Britain, by bombing London into rubble. The Nazi air campaign against London wasn't aimed at military objectives or logistical capacity. It was aimed at the minds and morale of the English people, to break them. Sherman had the same end in view. No Southerner will ever forgive him for bringing that crudity of a policy to bear on American civilians.
You won't win any points on this thread or any other by apologizing for William Sherman. Though I suppose you'll smoke out the South-haters as they surge forward gleefully to slap you on the back and join you in gloating.
But, since you bring up Sherman's rationale, let me quote from the contemporary British soldier/historian, Bevin Alexander:
(In Chattanooga) Sherman had come to realize that destroying the Southern people’s will to pursue the war was more important than destroying Johnston’s army. Once the people wearied of war, their armies would melt away. So long as they remained adamant, they would continue to throw up armies or, failing that, guerilla bands, which could lead to endless war. The only sure solution was to inflict so much damage on Southern property and way of life, and not merely “war resources,” that the people would prefer surrender to continued destruction.
I think ending the war as soon as possible was very much one of Sherman's goals. In his own words Sherman intended to convince the Southerners that "war and individual ruin and synonymous terms" and that "If they want peace, they and their relatives must stop war."
I find your comment, "No Southerner will ever forgive him (Sherman) for bringing that crudity of a policy to bear on American civilians," somewhat puzzling. If Robert E. Lee was correct when he noted in 1861, that "secession is revolution," do you consider Southerners as rebellious citizens of the USA, or enemy aliens to the USA? Citizens supporting enemy armies are simply treasonous. As civilians of an enemy country, did they deserve any better than the Germans or Japanese got 80 years later?
Admittedly, by the time Sherman got into South Carolina, his vendetta against the South became a vindictive opportunity to crush every last secessionist bone. General Halleck wrote to Sherman, "Should you capture Charleston, I hope by some accident the place may be destroyed, and, if a little salt should be sown upon its site, it may prevent the growth of future crops of nullification and secession." Sherman replied, "The whole army is buring with an insatiable desire to wreak vengence upon South Carolina. I almost tremble at her fate."
For the American generals, simply winning was no longer enough. Nevertheless, Sherman's approach to war, as compared to the barbaric frontal assaults used by Grant to pound Lee into submission, probably saved more American lives than it cost. But like Sherman said, "War is hell."