A like risk is almost always incurred by those who, on the approach of
an enemy, resolve to defend some place of strength, or to guard the
defiles by which their country is entered. For unless room be found in
this place of strength for almost all your army, the attempt to hold it
will almost always prove hurtful. If you can find room, it will be
right to defend your strong places; but if these be difficult of
access, and you cannot there keep your entire force together, the
effort to defend is mischievous. I come to this conclusion from
observing the example of those who, although their territories be
enclosed by mountains and precipices, have not, on being attacked by
powerful enemies, attempted to fight on the mountains or in the
defiles, but have advanced beyond them to meet their foes; or, if
unwilling to advance, have awaited attack behind their mountains, on
level and not on broken ground. The reason of which is, as I have above
explained, that many men cannot be assembled in these strong places for
their defence; partly because a large number of men cannot long subsist
there, and partly because such places being narrow and confined, afford
room for a few only; so that no enemy can there be withstood, who comes
in force to the attack; which he can easily do, his design being to
pass on and not to make a stay; whereas he who stands on the defensive
cannot do so in force, because, from not knowing when the enemy may
enter the confined and sterile tracts of which I speak, he may have to
lodge himself there for a long time. But should you lose some pass
which you had reckoned on holding, and on the defence of which your
country and army have relied, there commonly follows such panic among
your people and among the troops which remain to you, that you are
vanquished without opportunity given for any display of valour, and
lose everything without bringing all your resources into play.