6. The theater of war may be upon the soil of the enemy, upon that of an
ally, or upon its own.

7. If the war be one of invasion, it may be upon adjacent or distant
territory: it may be prudent and cautious, or it may be bold and
adventurous.

8. It may be a national war, either against ourselves or against the
enemy.

9. The war may be a civil or a religious war.

War is always to be conducted according to the great principles of the
art; but great discretion must be exercised in the nature of the
operations to be undertaken, which should depend upon the circumstances
of the case.

For example: two hundred thousand French wishing to subjugate the
Spanish people, united to a man against them, would not maneuver as the
same number of French in a march upon Vienna, or any other capital, to
compel a peace; nor would a French army fight the guerrillas of Mina as
they fought the Russians at Borodino; nor would a French army venture to
march upon Vienna without considering what might be the tone and temper
of the governments and communities between the Rhine and the Inn, or
between the Danube and the Elbe. A regiment should always fight in
nearly the same way; but commanding generals must be guided by
circumstances and events.

To these different combinations, which belong more or less to