Napoleon, now Emperor, was at Boulogne, threatening and perhaps at times half purposing an invasion of England. He commanded the best army he ever had. The Austrians, not supposing him ready, inundated Bavaria with troops, without waiting for their allies, the Russians, and marched up the Danube to the Iller, under Field-Marshal Mack. Napoleon put an embargo on the mails, broke up from Boulogne at twenty-four hours’ notice, and reached the vicinity of the enemy with an overwhelming force before Mack was aware of his having left the sea. His line of march was about Mack’s right flank, because this was the nearest to Boulogne and gave him a safe base on the confederate German provinces. So well planned was the manœuvre, so elastic in its design for change of circumstances, that it fully succeeded, step for step, until Mack was surrounded at Ulm and surrendered with his thirty thousand men. Here again we find the Napoleonic rule fairly overwhelming Mack with superior numbers. Except in 1796 and 1814, Napoleon always had more men than the enemy on the field at the proper time. “They ascribe more talent to me than to others,” he observed, “and yet to give battle to an enemy I am in the habit of beating, I never think I have enough men; I call to my aid all that I can unite.”
The chart herewith given of the grand manœuvre of Ulm is so simple as to suggest no difficulties of execution. But there is probably nothing in human experience which taxes strength, intellect, judgment, and character to so great a degree as the strategy and logistics of such a movement, unless it be the tactics of the ensuing battle. The difficulties are, in reality, gigantic.
Napoleon headed direct for Vienna, and on the way absolutely lived on the country. “In the movements and wars of invasion conducted by the Emperor, there are no magazines; it is a matter for the commanding generals of the corps to collect the means of victualling in the countries through which they march,” writes Berthier to Marmont. Napoleon took Vienna and marched out towards Brünn, where the Austrians and Russians had concentrated. Here he was far from secure, if equal talent had been opposed to him; but he took up a position near Austerlitz, from which he could retreat through Bohemia, if necessary, and, calmly watching the enemy and allowing several chances of winning an ordinary victory to pass, he waited, with an audacity which almost ran into braggadocio, for the enemy to commit some error from which he could wrest a decisive one. And this the allies did, as Napoleon divined they would do. They tried to turn his right flank and cut him off from Vienna. Napoleon massed his forces on their centre and right, broke these in pieces, and won the victory of which he was always most proud. Napoleon’s conduct here showed distinctly a glint of what he himself so aptly calls the divine part of the art.
There is always a corresponding danger in every plan which is of the kind to compass decisive results. In this case Napoleon risked his right wing. But to judge how much it is wise to risk and to guess just how much the enemy is capable of undertaking is a manifestation of genius.
The era of the great battles of modern war dates from Austerlitz. Marengo was rather two combats than one great battle. Frederick’s battles were wonders of tactics and courage, but they differ from the Napoleonic system. In Frederick’s battles the whole army was set in motion for one manœuvre at one time to be executed under the management of the chief. If the manœuvre was interrupted by unforeseen events, the battle might be lost. In Napoleon’s system, the centre might be broken and the wings still achieve victory; one wing might be crushed while the other destroyed the enemy. A bait was offered the enemy by the exhibition of a weak spot to attract his eye, while Napoleon fell on the key-point with overwhelming odds. But in this system the control passed from the hand of the leader. All he could do was to project a corps in a given direction at a given time. Once set in motion, these could not readily be arrested. Such a system required reserves much more than the old method. “Battles are only won by strengthening the line at a critical moment,” says Napoleon. Once in, Napoleon’s corps worked out their own salvation. He could but aid them with his reserves.
There is a magnificence of uncertainty and risk, and corresponding genius in the management of the battles of Napoleon; but for purely artistic tactics they do not appeal to us as do Frederick’s. The motif of Alexander’s battles is more akin to Napoleon’s; that of Hannibal’s, to Frederick’s.
It has been said that Napoleon never considered what he should do in case of failure. The reverse is more exact. Before delivering a battle, Napoleon busied himself little with what he would do in case of success. That was easy to decide. He busied himself markedly with what could be done in case of reverse.
Like all great captains, Napoleon preferred lieutenants who obeyed instead of initiating. He chafed at independent action. This was the chief’s prerogative. But as his armies grew in size he gave his marshals charge of detail under general instructions from himself. Dependence on Napoleon gradually sapped the self-reliance of more than one of his lieutenants, and though there are instances of noble ability at a distance from control, most of his marshals were able tacticians, rather than great generals. Napoleon grew impatient of contradiction or explanation; and he sometimes did not learn or was not told of things he ought to know. He was no longer so active. Campaigning was a hardship. His belief in his destiny became so strong that he began to take greater risks. Such a thing as failure did not exist for him. His armies were increasing in size, and railroads and telegraphs at that day did not hasten transportation and news. The difficulties he had to contend with were growing fast.
These things had the effect of making Napoleon’s military plans more magnificent, more far-reaching. But all the less could he pay heed to detail, and from now on one can, with some brilliant exceptions, perceive more errors of execution. In the general conception he was greater than ever, and this balanced the scale. His ability to put all his skill into the work immediately in hand was marvellous. But with a vast whole in view, the parts were, perhaps of necessity, lost sight of.
The campaigns of 1806 and 1807 were in sequence. To move on the Prussians, who, under the superannuated Duke of Brunswick, were concentrated in Thuringia, Napoleon massed on his own right, disgarnishing his left, turned their left,—in this case their strategic flank, because the manœuvre cut them off from Berlin and their allies, the Russians,—and with overwhelming vigor fell on the dawdling enemy at Jena and Auerstädt. The Prussians had remained stationary in the art of war where they had been left by Frederick, and had lost his burning genius.