19th Century Walls and Fortifications
The Wars of the Revolution and the Empire
Napoleon made use of fortifications either as supporting points for offensive maneuvers or as aids in holding important points with a small force. He classified them as barrier forts, for the defense of defiles and passes; frontier forts, for the protection of territory; depot forts, for the storage of supplies; and campaign forts, serving as pivots of maneuver. The last two he considered the most important. As to sea coast forts, he regarded them as purely defensive, for the protection of important harbors.
Napoleon did not allow himself to be tied to his own forts nor to be attracted by those of the enemy. He directed his operations toward a predetermined objective and gave to subordinate commanders the task of holding his own forts and observing those of the enemy. He followed this principle in 18o6, making the Prussian army his objective, and using fortified places merely as pivots of operations and supply depots. After the victories of Jena and Auerstadt Napoleon devoted his efforts to the pursuit of the scattered fragments of the Prussian army rather than to the reduction of Prussian forts.
In 1813 Napoleon abandoned his previous practice and allowed his army, already inferior to that of his enemies, to be weakened by the detachment of garrisons of 25,ooo at Hamburg, 3o,ooo at Dresden, 1o,ooo at Magdeburg, 3o,ooo in the forts of the Oder, and others in the forts of Italy and Dalmatia. The result was his defeat at Leipsic. The change of policy was dictated by political rather than military reasons. In the following year he expected the forts on the frontier to exercise a decided influence on the campaign by forcing the allies to detach large forces to observe the forts. This proved to be the case, but Napoleon would have fared better if he had not had the forts but had had their combined garrisons in hand for field operations.
The conclusion to be drawn from the Napoleonic wars is that fortifications, both permanent and temporary, exercised a great influence on the general plans of campaign, but that their influence on the actual progress of field operations was little or nothing, because Napoleon's maneuvers were always offensive.
The Wars for the Independence of Italy
After the downfall of Napoleon came a long period of peace lasting without serious interruption for more than thirty years. At the middle of the century the dominating ideas on the subject of fortifications were, first, the substitution of the polygonal for the bastioned system, and, second, the creation of intrenched camps composed of a central nucleus surrounded by a ring of detached forts, and capable of containing entire armies.
In 1848 Radetzky gathered his scanty forces in the fortresses of the Quadrilateral, where he reorganized his troops and awaited reinforcements. Here he based the plans which he later converted into action; here he awaited the attack of the Piedmontese army; and here he moved out to the counter attack by which he recovered what he had recently lost.
At that time the fortresses of the Quadrilateral were stone works, armed with guns in barbette. Peschiera was surrounded by small forts. Mantua had detached works and arrangements for inundation. Legnago was an important bridge head on the Adige. Verona was the most important, being a secure base for operations against the Mincio and towards the Tyrol.
The great need of Radetzky was to gain time. His opponents played into his hands by laying siege to the fortress instead of marching to cut off the reinforcements coming from Austria. The result was that Radetzky won and Charles AIbert lost.
After 1848 the Austrians continued to improve the fortresses of the Quadrilateral and these works became an important feature of the campaign of 1859. The campaign was stopped midway and the fortresses did not have time to exert their full influence on the field operations, but even before the campaign ended the Franco-Italian army, numerically inferior to the Austrian, had been divided into three parts to attack different fortresses. The Austrians committed similar errors in garrisoning other places that had no important bearing on the campaign. The justification for these steps must be sought in political reasons.
The War of 1866
In this war Austria decided to act on the defensive in the two theaters of war, the Bohemian-Moravian and the Italian, because she was opposed by superior numbers in each theater and was also surpassed in quickness of mobilization. In the first theater her concentration was based upon the fortress of Olmiitz, which was intended to cover Vienna. The Prussian advance into Bohemia forced Benedeck to abandon Olmiitz. After his defeat at Sadowa he returned to Olmiitz. Von Moltke left an army to observe him and moved on Vienna. Before the subsequent field operations were fully developed they were ended by an armistice.
In the Italian theater the concentration was based upon the Quadrilateral, and this fortified region exercised a great influence on the operations, not so much on account of its intrinsic importance as by the effect it had on the mind of Lamarmor'a. There were two courses of action open in dealing with the Quadrilateral, to make a direct attack on it or to go around it and advance on Venice. Unfortunately, the course adopted was a division of forces and an attempt to do both. The result was the defeat of the Italians at Custozza.
The Franco-German War of 1870-71
In this great war the French fortresses exercised a capital influence on both the strategical and the tactical developments. They rendered services of the highest importance to the French, but at the same time they exercised an irresistible and injurious force of attraction upon the French commanders and even upon the men. They did not have this influence upon the Prussians. Von Moltke did not concern himself overmuch with fortified places. He left detachments to besiege them, but he moved on with the main force. Paris was besieged in force not because it was a fortified place but because it was the capital and the heart of France. And von Moltke was prepared to withdraw the bulk of the besieging forces from Paris if that course had become necessary in order to meet new armies in the field.
The loss of Bazaine's army at Metz is a notable illustration of the baleful attraction exercised by a fortress. Political conditions entered into the problem, as a continued retreat meant the abandonment of large areas of the soil of France to the invader. The correct use of the fortress would have been made by occupying it with a small fraction of the army, delaying the enemy, forcing him to make a detachment to observe the fortress, and thereby gaining time for the main force to continue the retreat and receive reinforcements. One important service rendered by the fortresses was the blocking of a number of railroad lines which would have been of great value to the Prussians. The importance of the fortresses to the French would have been much increased if they had been better prepared and better defended.
The Russo-Turkish War (1877-78)
In this war the offensive was taken by Russia. Her principal objective was Constantinople, to reach which three barriers had to be passed. The first was the Danube; the second was the Balkans; the third was the line of Tschatalja, where the Turks had constructed some temporary works, which were not defended.
The best line of action for the Turks would have been to oppose the crossing of the Danube. Instead of doing this, the Turks kept their principal army shut up in Bulgarian fortresses. Likewise, the army of Osman Pasha allowed itself to be shut up in Plevna, where it made a magnificent defense but perished nevertheless. Each force occupying a fortress succeeded in holding the attention of a force of the enemy several times its own size, but the Turks could not accomplish any decisive result in this way. They should have risked a battle in the open.
The Russians erred in besieging the fortresses instead of merely observing them. Even Plevna could have been treated in this way, leaving large numbers of men available for the advance on Constantinople. As a general conclusion, the effect of the fortresses on both combatants was negative and unfavorable.
The Anglo-Boer War
This war brought out two opposing strategical concept1ons, represented by Sir Redvers Buller and Lord Roberts. The first believed in subordinating field operations to fortified places, and the second in making field operations independent of such places. The result 'proved the wisdom of making the hostile army the real objective.
During the first period of the war, the chief concern of Buller was the relief of the forces besieged in Kimberly and Ladysmith. For this purpose he divided his forces into two parts entirely independent of each other, with the result that each found itself inferior in numbers to its adversary.
In the second period of the war under Lord Roberts, the British took the offensive against the Boers in the field, and succeeded in not only causing the Boers to raise the sieges of Kimberly and Ladysmith, but also putting an end to the Boer offensive.
The campaign in the Transvaal was the last great war of the nineteenth century, but as the campaigns in Manchuria and the Balkans did not differ strategically from those of the preceding century it is instructive to make note of them.
The Russo-Japanese War in Manchuria (1904-1905)
The fortress to be considered in this war is Port Arthur. It was primarily a seacoast fort, strong on the side toward the water but weak on the land side. Two plans of campaign were open to the Japanese, to seize at once the territory that had been the bone of contention previous to the conflict, and then turn on the combatant force of the enemy; or to profit by numerical superiority and move against the enemy at once, and then take possession of the territorial objective. Counting on the weakness of Port Arthur, the Japanese adopted the first solution. They occupied Korea and then sent a force against the fortress. The separation of forces resulting from this plan and the unexpected resistance of the fortress would have had serious consequences for Japan had Russia had the capacity to take advantage of her opportunities.
On the Russian side there was a conflict of opinion between the Viceroy Alexieff and General Kuropatkin. The former wished to send troops to the relief of the fortress. The latter was confident that the fortress could hold out for a long time, and proposed to leave it to its fate for a time so as to make thei field army independent in its operations. The views of the Viceroy prevailed and reinforcements were sent toward Port Arthur.
Both armies were weakened by the detachments they sent to besiege or relieve Port Arthur, and neither was able to gain a decisive victory in the field.
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