"I will hold the town till we starve," Thomas replied, and they almost did starve. Cut off from supplies, his army was living on half rations. Thousands of horses and mules died. Weeks passed before Grant assembled strength sufficient to lift the siege. The key terrain was towering Missionary Ridge. Grant ordered Sherman to drive onto the ridge from the left and Maj. Gen. Joseph Hooker from the right, with Thomas aimed at the center. Sherman tried and failed to carry his end, but Hooker's troops took Lookout Mountain on the far flank. Thomas waited for Grant's order to advance. When it came, Thomas took his time studying the crest with his binoculars, then sent his troops ahead with orders to occupy only the first line of the Confederate works. They did so in fine style—and then, seeing that they were exposed to fire from above, kept going. Thomas was surprised and Grant angry, demanding "Who ordered those men up the hill?" No one had. The troops plunged ahead, pressing on against heavy fire, struggling up the steep slope and jubilantly planting their flag on the heights for all to see.
Assistant Secretary of War Charles A. Dana, an eyewitness, called the assault "one of the greatest miracles in military history....as awful as a visible interposition of God." Thomas, moved by the sight, ordered that a cemetery be created for his soldiers on a beautiful slope of the battlefield. When a chaplain asked if the dead should be separated by state, Thomas did not hesitate. "No, no," he said. "Mix them up. Mix them up. I'm tired of states' rights." Once he had made up his mind to stay with the old flag, he never expressed misgivings; if he had them, they had long been erased by seeing so many men die to preserve the Union.
By late 1883, U.S. Colored Troops were filling some of the gaps opened in Federal forces by battle and disease. Although Sherman had resisted using black soldiers, Thomas gladly accepted them. In the drastic move from serfdom to freedom, he wrote, it was probably better for ex-slaves to be soldiers, and thus gradually learn to support themselves, than "to be thrown upon the cold charities of the world without sympathy or assistance."
As the Federals gathered strength to thrust into Georgia, this was not the only disagreement between the tightly strung Ohioan and the calm Virginian. In early March, Lincoln called Grant east to become general in chief of all Northern armies. No one was surprised that Grant's friend Sherman, rather than Thomas, replaced him as commander in the West, even though as a major general Thomas was senior to Sherman. Ex-colonel Donn Piatt, a 19th-century booster and biographer of Thomas, called it "the nakedest favoritism that ever disgraced a service."
At the start of his 1864 drive toward Atlanta, Sherman rejected Thomas' plan to take his command through Snake Creek Gap to cut off and smash Joseph Johnston's Confederate army. More than a month into Georgia, an impatient Sherman complained to Grant that Thomas' Army of the Cumberland was slowing his advance—"a fresh furrow in a plowed field will stop the whole column." He was still in this mood a few days later when he ignored Thomas' advice against attacking the strongly entrenched Rebels head-on at Kennesaw Mountain. The Federals lost more than 2,000 troops in trying to take what Thomas had warned was an impregnable position.
Thomas commanded about two-thirds of Sherman's infantry; his army was the center force, the sledgehammer in the four-month campaign, and led the way into Atlanta. But neither Sherman, Grant, Secretary of War Edwin Stanton nor Lincoln cited Thomas in their congratulations. As in the 1864 Virginia campaign, where all the official praise and headlines went to Grant, in Georgia it was all Sherman. In his special order announcing the victory, Sherman credited Maj. Gen. Henry W. Slocum's corps with entering the city first—although Slocum was under Thomas' command and had headed the corps for only six days.
When Atlanta's mayor protested Sherman's harsh military rule, the general replied, "War is cruelty and you cannot refine it...those who brought war into our country deserve all the curses and maledictions a people can pour out....You might as well appeal against the thunderstorm." Then he set out on his storied march to infamy and greatness, pillaging the countryside as he cut a great swath through the Confederacy.
Thomas took a different view. Stern though he was in combat, he posted a guard at the house of a citizen suspected of disloyalty because, he said, "We must remember that this is a civil war, fought to preserve the Union that is based on brotherly love and patriotic belief in the one nation....The thing becomes horribly grotesque...when we visit on helpless old men, women, and children the horrors of a barbarous war. We must be as considerate and kind as possible, or we will find that in destroying the rebels we have destroyed the Union."
Opposite in personality, tactics and philosophy, Thomas and Sherman were thereafter gratefully separated in geography as well. While Grant grappled with Lee in Virginia and Sherman gutted the eastern Confederacy, Thomas was sent back to Tennessee to reorganize the stripped-down Army of the Cumberland and deal with Hood. The Confederate general had got away from Atlanta with some 40,000 troops and evaded Sherman's effort to catch him. Now he was marching north through Tennessee. Thomas' Federals under John Schofield slowed and badly damaged the Rebels in the fierce battle of Franklin, but by December Hood was dug in on the high ground facing Nashville. Thomas fortified the city while he gathered strength for a decisive blow, but to carry it out he needed more men, horses and supplies.
Grant, 500 miles away, grew impatient. He sent telegrams urging Thomas to move, then ordered him to "attack at once." Thomas said after the war that he was tempted—"grossly improper as it would have been"—to ask why Grant himself, who was entrenched around Petersburg, was not fighting. Defeat at Nashville "would have been a greater calamity than any which had befallen the Federal forces," he said. "It would have cleared the way for the triumphant march of Hood's army through Kentucky, and a successful invasion of Indiana and Illinois, in which there were no Federal troops. It was therefore of the last importance that the battle upon which so much depended should not be fought until I was ready for it." Thomas continued planning, training, stocking—equipping his horsemen with the new breech-loading Spencer carbines.