Thus considered, the principles of tactics look simple enough. However, it is one thing to analyze tactics in the abstract but entirely another thing to put theory into practice under different circumstances, on different kinds of terrain, against different kinds of enemy, with the aid of troops who may be tired or confused or recalcitrant, and amid every kind of mortal danger. As the great Prussian general Carl von Clausewitz said, “In war everything is simple, but even the simplest thing is difficult.” Sophisticated tactics require well-trained, articulated forces consisting of different units that are armed with different weapons and possess different capabilities. Next, these units must be subordinated to a single directing brain and must be employed in a coordinated manner following a single, well-considered plan: hence the principle of unity of command.

Even then, tactics are not just a question of executing a plan, however clever and well conceived. In tactics, even more than elsewhere, a commander who can only make a plan and carry it out avails nothing; inasmuch as he is confronting a living enemy, what matters is his ability to adapt the plan to that enemy’s reactions rapidly, smoothly, and without losing his grip. Flexibility is thus a cardinal principle of tactics. But flexibility will prevail only if it can be bound by a firm disciplinary framework. Moreover, flexibility and discipline are not easy to combine and can often be achieved only at each other’s expense. Other things being equal, the larger and more powerful a given force, the less flexible it will be.

As an armed force exchanges blows with an enemy, adapting to his moves and forcing him to adapt in return, opportunities to take him by surprise should present themselves. Surprise presupposes secrecy, but secrecy may be hard to combine with the rapid action that is often necessary for implementing surprise. Like everything else in tactics, overcoming this paradox is a matter of striking a balance, first in general and then against a specific enemy, under specific circumstances and with a specific objective in mind.

The importance of terrain

Finally, in tactics (as in strategy) there is the topographical element to consider. Land warfare is fought neither in a vacuum nor on a uniformly checkered board. Instead, it unfolds over concrete terrain, including roads, passages, elevated ground, cover, and obstacles of every kind. Victory goes to him who best understands and utilizes the terrain; this may be done by, for example, occupying dominant ground, utilizing cover, compelling the enemy to fight on terrain for which his forces are not suitable, cornering him, outflanking him, or surrounding him. All these methods are as old as warfare, yet at the same time they remain relevant to the present age. On their correct application the outcome of battle depends.