The opening period of the campaign had developed the conditions of warfare in so broken and difficult a country, and they were only emphasized by the later experiences of both armies. Positions for defence could be intrenched with field-works whilst the hostile army was feeling its way forward through dense forests and over mountain ridges. To carry such positions by direct assault was so costly that the lesson of prudence was soon learned and such attacks were more and more rarely resorted to. Sherman had moved upon the enemy at Resaca as promptly as the deployment and advance could be made after the turning movement and the passage of the Snake Creek defile; but we found Johnston strongly placed, on ground naturally difficult of approach, with works which gave his men such cover as to overcome any advantage we had in numbers. Still, the enemy found in turn that we could make counter-intrenchments and quickly extend them till we turned his flanks and threatened his communications, when he must either retreat or assault our works, and that, if he assaulted, the balance of losses would turn so heavily against him as to fatally deplete his army. Johnston carefully and systematically maintained this defensive, and in Virginia, after Lee had tried the policy of attack in the Wilderness, he became as cautiously defensive as Johnston. Grant was slower than Sherman in learning the unprofitableness of attacking field-works, and his campaign was by far the more costly one. The difference in such cases goes much farther than the casualty list; it was shown in October, when Sherman's army was strong and well-seasoned, but Grant's was so full of raw recruits as almost to have lost its veteran quality. There were special reasons which led Grant to adhere so long to the more aggressive tactics, which would need to be weighed in any full treatment of the subject; but I am now only pointing out the fact that in both the East and the West the lesson was practically the same. Aggressive strategy had the advantage it always has, but defensive tactics proved generally the better in so peculiar a field of operations.