try from which the army
obtains its reinforcements and resources, from which it starts when it
takes the offensive, to which it retreats when necessary, and by which
it is supported when it takes position to cover the country defensively.

The base of operations is most generally that of supply,--though not
necessarily so, at least as far as food is concerned; as, for instance,
a French army upon the Elbe might be subsisted from Westphalia or
Franconia, but its real base would certainly be upon the Rhine.

When a frontier possesses good natural or artificial barriers, it may be
alternately either an excellent base for offensive operations, or a line
of defense when the state is invaded. In the latter case it will always
be prudent to have a second base in rear; for, although an army in its
own country will everywhere find a point of support, there is still a
vast difference between those parts of the country without military
positions and means, as forts, arsenals, and fortified depots, and those
other portions where these military resources are found; and these
latter alone can be considered as safe bases of operations. An army may
have in succession a number of bases: for instance, a French army in
Germany will have the Rhine for its first base; it may have others
beyond this, wherever it has allies or permanent lines of defense; but
if it is driven back across the Rhine it will have for a base either the
Meuse or the Moselle: it might have a third upon the Seine, and a fourth
upon the Loire.

These successive bases may not be entirely or nearly parallel to the
first. On the contrary, a total change of direction may become
necessary. A French army repulsed beyond the Rhine might find a good
base on Befort or Besancon, on Mezieres or Sedan, as the Russian army
after the evacuation of Moscow left the base on the north and east and
established itself upon the line of the Oka and the southern provinces.
These lateral bases perpendicular to the front of defense are often
decisive in preventing the enemy from penetrating to the heart of the
country, or at least in rendering it impossible for him to maintain
himself there. A base upon a broad and rapid river, both banks being
held by strong works, would be as favorable as could be desired.

The more extended the base, the more difficulty will there be in
covering it; but it will also be more difficult to cut the army off from
it. A state whose capital is too near the fron