On page 240 we have this careful estimate of the situation at the beginning of September:
On the seventh of September I learned of the advance of Van Dorn and Price, apparently upon Corinth. One division was brought from Memphis to Bolivar to meet any emergency that might arise from this move of the enemy. I was much concerned because my first duty after holding the territory acquired within my command, was to prevent further reinforcing of Bragg in Middle Tennessee. Already the army of Northern Virginia had defeated the army under General Pope, and was invading Maryland. In the center General Buell was on his way to Louisville and Bragg marching parallel to him with a large Confederate force for the Ohio river. I had been constantly called upon to reinforce Buell until at this time my entire force numbered less than 50,000 men of all arms. This included everything from Cairo south within my jurisdiction. If I too should be driven back the Ohio river would become the line dividing the belligerents west of the Alleghanies while at the east the line was already farther north than when hostilities commenced at the opening of the war. It is true Nashville was never given up after its first capture, but it would have been isolated and the garrison there would have been obliged to beat a hasty retreat if the troops in West Tennessee had been compelled to fall back. To say, at the end of the second year of the war the line dividing the contestants at the east was pushed north of Maryland, a state that had not seceded, and at the west beyond Kentucky, and this State which had been always loyal, would have been discouraging indeed. As it was many loyal people despaired in the Fall of 1862 of ever saving the Union. The Administration at Washington was much concerned for the safety of the cause it held so dear.
This was a most trying time for a man of General Grant's overmastering instinct of activity. The task set him of guarding a vast territory and three railroad lines against a ceaselessly active and enterprising enemy, gave him occupation enough it is true. But the situation forbade him to concentrate anywhere, or to do anything indeed except repel assaults first upon one insignificant point and then upon another. A mere catalogue of the actions fought at this time in that quarter would occupy pages of print. Only one of them had enough significance to require mention in this history. On the thirteenth of September the Confederate general, Sterling Price, with a considerable force occupied Iuka, a town on the Memphis and Charleston railroad, about twenty miles east of Corinth. The fact was a significant commentary upon the unwisdom of the orders which delayed Buell's march on Chattanooga, in the end defeating its purpose, in order to repair a railroad, any point upon which the Confederates could seize at will in spite of Grant's utmost diligence in an impracticable and indeed impossible defense.