Both Grant and Sherman shared the same theory of war: anything that might help the enemy's war effort should be considered a military target. After the Atlanta campaign, Grant explained to Sherman that the Confederates must be "demoralized and left without hope," and he instructed Sherman, "Take all provisions, forage and stock wanted for the use of your command. Such as cannot be consumed, destroy. Leave the valley so barren that crows flying over it...will have to carry their provender with them." This strategy sought the total economic collapse of the South, as well as completely disabling the South's capability of fielding armies. In addition to the wholesale plundering of Southern resources, including taking them from civilians, the Union reversed its policy of swapping prisoners, realizing it had a far bigger reserve of manpower than the South. The Atlanta Campaign was a perfect example of this, as both sides lost about the same number of casualties. By September 1864, however, Sherman still had about 80,000 men, while Hood's army was reduced to about 30,000.

Following the design of Grant's innovative and successful Vicksburg Campaign, Sherman's armies eliminated their need for traditional supply lines by living off the land. Ultimately, Sherman's armies cut a path of abject destruction 60 miles wide and 300 hundred miles long from Atlanta to Savannah, which some likened to a Biblical blight. And as Sherman had intended, he did indeed made Georgia "howl." 

Due in large part to the March to the Sea, Sherman remains controversial across much of the United States today. The South considered him akin to a terrorist and adamantly insisted that he was violating the norms of warfare by targeting civilians. In many ways, Sherman is still the scourge of the South nearly 160 years after he vowed to make Georgia howl.