2. The influence of mountains on other parts of the country.
Because, as we have seen, it is so easy in mountainous ground to secure a considerable tract of territory by small posts, so weak in numbers that in a district easily traversed they could not maintain themselves, and would be continually exposed to danger; because every step forward in mountains which have been occupied by the enemy must be made much more slowly than in a level country, and therefore cannot be made at the same rate with him therefore the question, Who is in possession? is also much more important in reference to mountains than to any other tract of country of equal extent. In an open country, the possession may change from day to day. The mere advance of strong detachments compels the enemy to give up the country we want to occupy. But it is not so in mountains; there a very stout resistance is possible by much inferior forces, and for that reason, if we require a portion of country which includes mountains, enterprises of a special nature, formed for the purpose, and often necessitating a considerable expenditure of time as well as of men, are always required in order to obtain possession. If, therefore, the mountains of a country are not the theatre of the principal operations of a war, we cannot, as we should were it the case of a district of level country, look upon the possession of the mountains as dependent on and a necessary consequence of our success at other parts.
A mountainous district has therefore much more independence, and the possession of it is much firmer and less liable to change. If we add to this that a ridge of mountains from its crests affords a good view over the adjacent open country, whilst it remains itself veiled in obscurity, we may therefore conceive that when we are close to mountains, without being in actual possession of them, they are to be regarded as a constant source of disadvantage a sort of laboratory of hostile forces; and this will be the case in a still greater degree if the mountains are not only occupied by the enemy, but also form part of his territory. The smallest bodies of adventurous partisans always find shelter there if pursued, and can then sally forth again with impunity at other points; the largest bodies, under their cover, can approach unperceived, and our forces must, therefore, always keep at a sufficient distance if they would avoid getting within reach of their dominating influence if they would not be exposed to disadvantageous combats and sudden attacks which they cannot return.
In this manner every mountain system, as far as a certain distance, exercises a very great influence over the lower and more level country adjacent to it. Whether this influence shall take effect momentarily, for instance in a battle (as at Maltsch on the Rhine, 1796) or only after some time upon the lines of communication, depends on the local relations; whether or not it shall be overcome through some decisive event happening in the valley or level country, depends on the relations of the armed forces to each other respectively.
Buonaparte, in 1805 and 1809, advanced upon Vienna without troubling himself much about the Tyrol; but Moreau had to leave Swabia in 1796, chiefly because he was not master of the more elevated parts of the country, and too many troops were required to watch them. In campaigns, in which there is an evenly balanced series of alternate successes on each side, we shall not expose ourselves to the constant disadvantage of the mountains remaining in possession of the enemy: we need, therefore, only endeavour to seize and retain possession of that portion of them which is required on account of the direction of the principal lines of our attack; this generally leads to the mountains being the arena of the separate minor combats which take place between forces on each side. But we must be careful of overrating the importance of this circumstance, and being led to consider a mountain-chain as the key to the whole in all cases, and its possession as the main point. When a victory is the object sought; then it is the principal, object; and if the victory is gained, other things can be regulated according to the paramount requirement of the situation.