Grant's Secret Service: The Intelligence War from Belmont to Appomattox

5. "With All the Vigilance I Can Bring to Bear I Cannot Determine the Objects of the Enemy"

Chapter 5 ‘‘With All the Vigilance I Can Bring to Bear I Cannot Determine the Objects of the Enemy’’ For several weeks after Shiloh, both sides tended their wounded, buried the dead, and prepared for the next bout. Henry W. Halleck arrived at Pittsburg Landing and took charge of the upcoming offensive against Corinth. As punishment for the recent near-disaster, Grant watched from the sidelines as Halleck directed the next campaign. Fearing another surprise and anxious to fight war according to the book, ‘‘Old Brains’’ advanced south cautiously and at glacial speed, entrenching at every stop. At this ponderous pace, it took nearly a month to traverse the twenty-two miles to Corinth. On May 30 the Confederates evacuated the rail junction without a fight and retreated south to Tupelo, which caused the abandonment of Memphis. Elevated to the post of general in chief of all Union armies, in mid-July Halleck hurried to Washington, once again leaving Grant in overall command of operations in the Mississippi Valley. Before his departure, however, Halleck had dispersed his combined armies in northern Mississippi and western Tennessee to safeguard the Union’s recent gains. To make matters worse, in mid-June, Don Carlos Buell’s Army of the Ohio departed on a mission to seize Chattanooga and East Tennessee. When Grant arrived in Corinth on July 17, his scattered force, consisting of 63,709 men in the Army of the Tennessee and the Army of the Mississippi, guarded a front 115 miles long and protected over 360 miles of track. In addition to chasing ubiquitous guerrillas, rebuilding railroad bridges, replacing torn-up track, and managing an overtly hostile population, Grant had to monitor enemy forces fifty miles farther south at Tupelo. The loss of the initiative after the Corinth campaign , sealed by Halleck’s decision to disperse the army, not only forced Grant to defend a far-flung command but also placed the burden of uncertainty back on his shoulders. Forced into a situation he despised, he had little choice but to determine and react to the enemy’s moves as best he could. ‘‘In this he was only manifesting one of his chief military characteristics ,’’ wrote staff officer Horace Porter, ‘‘an inborn dislike to be thrown upon the defensive.’’ Until he consolidated his armies for an offensive , the Confederates could strangle his logistical lines and pounce on isolated garrisons. In this situation, intelligence would become a critical necessity in protecting his scattered forces.1 From the beginning of his tenure, however, Grant encountered diffi109 culties meeting his intelligence needs. First, communications between posts remained tenuous; guerrillas and Confederate cavalry severed telegraph wires, interrupted rail traffic, and captured Union couriers.2 Second , the lack of a centralized armywide intelligence service left this task in the hands of individual field commanders, whose efforts depended heavily upon their attitude toward the ‘‘business’’ and their own past experiences.3 Fortunately for Grant, several subordinates understood the importance of gathering information on the enemy and worked tirelessly to procure it. Sherman, now head of the District of Memphis, had learned a lesson at Shiloh and began dispatching scouts and spies regularly . Brig. Gen. William S. Rosecrans, commanding the Federal Army of the Mississippi, brought his keen organizational skill to bear upon secret service operations, which would profoundly influence future operations in the region. Rosecrans received permission from Halleck to ‘‘arrange his scouts and cavalry movements’’ completely independent of direction from headquarters, an arrangement Grant honored.4 When Grant assumed command, he not only needed intelligence on the enemy but also had to prevent the Confederates from getting information on him. Counterintelligence problems had vexed him during his brief stay in Memphis in June 1862 when the activities of prosecession civilians made life difficult for Union occupiers. At the time, he complained , ‘‘spies and members of the southern army are constantly finding their way in and out of the city in spite of all vigilance.’’ This frustration led him to take the drastic measure of expelling all families of soldiers and officials in Confederate service from the city. The problem followed Grant to his new headquarters in Corinth. According to Rosecrans, the enemy apparently believed ‘‘our guards about Corinth are badly posted’’ and took advantage of it. As a result, he warned, ‘‘their spies go where they please.’’ On the defensive and widely spread out, Grant vowed to staunch this potential information hemorrhage. On July...