all is when two independent Commanders of armies of different powers find themselves on the same theatre of war, as frequently happened in the Seven Years’ War with the armies of Russia, Austria, and the German States. When there is a complete separation of forces, the burdens which must be borne are also better divided, and each suffers only from what is his own, consequently is more impelled to activity by the force of circumstances; but if they find themselves in close connection, or quite on the same theatre of war, this is not the case, and besides that the ill will of one paralyses also the powers of the other as well.
In the first of the three supposed cases, there will be no difficulty in the complete separation, as the natural interest of each State generally indicates to it a separate mode of employing its force; this may not be so in the second case, and then, as a rule, there is nothing to be done but to place oneself completely under the auxiliary army, if its strength is in any way proportionate to that measure, as the Austrians did in the latter part of the campaign of 1815, and the Prussians in the campaign of 1807.
With regard to the personal qualifications of the General, everything in this passes into what is particular and individual; but we must not omit to make one general remark, which is, that we should not, as is generally done, place at the head of subordinate armies the most prudent and cautious Commanders, but the most enterprising; for we repeat that in strategic operations conducted separately, there is nothing more important than that every part should develop its powers to the full, in that way faults committed at one part may be compensated for by successes at others. This complete activity at all points, however, is only to be expected when the Commanders are spirited, enterprising men, who are urged forwards by natural impulsiveness by their own hearts, because a mere objective, coolly reasoned out, conviction of the necessity of action seldom suffices.