Rightly interpreted, there was no greater strategy in all the war than this. Yet nothing has been more misunderstood or more injuriously reported. In his uncertainty as to whether Lee would accept battle in the open field, or would fall back upon Richmond and defend that city behind strong earthworks, Grant prepared himself for either contingency. He ordered Butler, with a strongly reinforced army, to move up the southern side of James river, supported by the gunboats, and to establish himself in an unassailable position, from which, in case of Lee's declining battle in the open, he might threaten or assail the southern and eastern defenses of the Confederate capital, while Grant, with the Army of the Potomac, might fall upon that city from the North, thus bringing to bear against Lee a combined force three or four times as great as his own. But his strong hope was that Lee would accept battle in the field, and that the Confederate general might be so far crippled there by the assaults of overwhelming numbers as to be far less formidable in his final defense of Richmond than he must be if forced back to that position by maneuvering and without fighting. If there was any error or miscalculation in General Grant's plan for the destruction of the Confederacy and the ending of the war, that error was in underestimating the tremendous fighting force of the Army of Northern Virginia, under command of Robert E. Lee. Grant had never met Lee in battle, and had learned of his capacity and of the resisting power of the army under his command only by hearsay. These were so much greater than anything else of the kind that had been known in the war that Grant's mistake, if he made any mistake, was surely pardonable. He had reckoned rightly in supposing that Sherman could deal successfully with Johnston, could take Atlanta, and could push his army thence to the sea, again cutting in twain what remained of the Confederacy. Perhaps he had not fully appreciated the resisting capacity of Lee with his Army of Northern Virginia. Perhaps he had a trifle too confidently reckoned upon numbers as a means of crushing that force. At any rate in his tremendous campaign from the Wilderness to Petersburg, he did not conquer it or crush it. So far indeed did he fail to do this, that after Lee had retired to Richmond and Petersburg and there confronted Grant's enormously reinforced army, the Confederate general was able to reinforce Early in the valley and send him on an expedition northward which threw Washington again into a panic, and for a time threatened the compulsory withdrawal of a part of Grant's forces from the siege of Richmond and Petersburg.