The Defense
I have said over and over that the offense is the decisive form of war, that you cannot win a war from the defensive. I hope I have explained it well enough for you to accept it as true--just as in football, you can't win unless you are moving forward.
That said, there are times when the right course of action is for an army to defend rather than attack, to offer a target and give the enemy a chance to exhaust himself before assuming or resuming the offense. You may do this if you have just conducted a successful offensive, but fallen short of complete victory and need time to consolidate your gains and bring up fresh forces to continue the attack. You may have just seized a piece of key terrain and expect the enemy to counterattack to take it back. Or you may be trying to regain the initiative after a successful enemy offensive. Or you may be protecting your last refuge, or your home, or your capital city from an enemy attack. Etc, etc. You get the picture. The bottom line is that in most cases, defense is a temporary measure, a chance for the defender to get his feet back under him so he can start moving forward again.
Note: there are examples from history, especially from the middle ages and the early modern period (1500s-1600s), of attacking forces lifting their attacks without the defenders taking offensive action. In most cases, this is due to outside influences (disease or famine among the attackers' ranks, or attacks by third parties against the attackers or sites of importance to them) or to unilateral action on the attackers' part (impressed by the defenders' valor and bound by the code of ethics of the day, the attackers decide to let them live and go home). Do not mistake these for decisive victories on the part of the defenders--they cannot, strictly speaking, be said to have won the battle, only survived it. Any "victory" in which one side chooses to leave the field on his own initiative, other than under imminent threat of destruction or defeat, cannot be called decisive.
Do not be fooled into thinking the defense will give your characters a chance to rest, either. The defense is "restful" only in comparison with the offense, and only because your soldiers get to stay in one place for a little while. Preparing a successful defense is difficult; it requires hard labor, intricate planning and reconnaissance, and constant alertness. It will leave your characters exhausted, and apprehensive, especially if they are preparing their defense under direct or indirect enemy pressure. And when it comes to the fight, any competent defending commander will be biting his nails because he knows where he is weak and is praying the enemy does not find the seams in his defense. There is never enough time to do everything.
Nor is the defense a passive activity. You cannot just sit in your strong position and wait for your enemy to come to you; you must aggressively seek to disrupt his offense, with obstacles or spoiling attacks or long-range weapons, and you must take active measures to ensure he hits you where you want him to, rather than allowing him to pick the site of his attack. And as with the attack, intelligence is critical: not only must you know where he is and how he plans to come at you, you must stop him from learning your exact positions and dispositions.
Characteristics of the Defense:
Preparation: Preparation is constant and unrelenting. The defender is always improving his position, right up to the point he makes contact with the enemy or leaves the position. Even while one part of the defense is in contact with the enemy, another part can be continuing its preparations.
Preparation for the defense includes selecting and improving the ground you mean to fight on, using natural and pre-existing obstacles and supplementing them with earthworks, walls, barricades, tree trunks, barbed wire, mines, asteroids--whatever your characters have at their disposal based on their situation and technological level. It includes familiarizing yourself with every inch of the terrain you mean to fight on, determining how your enemy can approach you and what you can do to thwart him before he gets to you. And it includes making every defender familiar with your obstacles through terrain walks, rehearsals, and sighting in weapons systems if appropriate. If your defenders are using ranged weapons, they should know the distances to various points on the ground, either by using natural landmarks or manmade markers. If their defense will require resupply at some point, they must prepare and secure safe routes for the supply vehicles to come up from the rear.
Security: As we discussed above, intelligence is critical: know where your enemy is, what he has, and how he must come at you. Other security considerations include false positions or blocking positions to make the enemy think you mean to defend somewhere other than your actual position, and perhaps even feints or demonstrations to deceive him as to your strength and purpose.
Disruption: Part of defeating an enemy's attack is not allowing him to execute his plan. You can disrupt his attack with spoiling attacks, ambushes, obstacles, deceptive movements, long-range weapons, and any other measures that may occur to you. Defeating his reconnaissance--blinding him, so to speak, so he has to feel his way to your position--is an excellent way to disrupt his tempo.
Massing Effects: You want your enemy to go where it is easiest for you to kill him. Use the terrain and your obstacles to channel him into areas free of cover that you can reach with multiple weapons systems or hidden forces, in which he has no place to hide. Anywhere the terrain is constricted--a bridge, a canyon, a mountain pass--is ideal for this purpose. For pre-gunpowder armies, a castle wall is an excellent example: as attackers try to climb or breach the wall, defenders can attack them with arrows, spears, stones, hot liquids, and fire.
Flexibility: Even if you take every precaution, there is no guarantee the enemy will go where you want him to go or do what you want him to do. You must be able to adjust your plan to meet his attack as it develops, not as you think it will develop. After all, he has read yesterday's post and he knows to try to hit your weaknesses with his strengths. If your position is strong enough, he may even try to avoid it altogether.
Types of Defensive Operations:
Mobile Defense: A mobile defense maximizes the defender's flexibility and, if successful, can make the transition to the offense almost seamless. This is the defensive version of the frontal attack-envelopment combination we discussed two days ago; a small defending force occupies a strong position, with another (usually larger) counterattack force hidden nearby. When the enemy commits his attack against the defensive position, the counterattack force hits him on the flank or rear. Obviously, this form of defense requires a high degree of coordination between the two forces, as well as excellent mobility on the part of the counterattack force. The mobile defense is usually not feasible for small units, but for large formations it is potentially the most destructive form of defense--a strong counterattack can achieve a decisive victory for the defender.
Area Defense: This is what most people think of when they think of a defense. An area defense focuses most of the defenders' strength on holding a piece of ground; it is a trade of "bodies for land," as a commander of mine used to say. Again, this need not be a static defense in one place; maximize disruption and massing effects in order to foil the enemy's attack and inflict casualties before he reaches your defensive position, and remain flexible so you can counterattack at the opportune moment.
Retrograde: If area defense trades bodies for land, a retrograde trades land for bodies. The retrograde force is moving backward, away from the enemy, either in contact or out of contact. Its function is either to put space between itself (or another force) and the enemy, or to slow his advance so other forces can prepare their defenses. There are three types of retrograde operation:
1) Withdrawal. A withdrawing force attempts to disengage from contact with the enemy, either to allow another force to assume its mission or to occupy another position to its rear.
2) Delay. A delaying force moves away from the enemy, but maintains contact. As the name suggest, its mission is to slow the enemy, either to draw him into an area where other friendly forces can counterattack or to allow forces behind to prepare their defenses, or both.
3) Retirement. A retirement occurs when a force not in contact with the enemy leaves its position and moves to the rear, either to occupy another defensive position or to allow another unit to assume its mission.
A final note on the defense: gravity is your friend. Unless, of course, you are defending a planet and establish a ring of asteroids to use as obstacles, which your enemy then proceeds to dislodge from orbit and rain down on your planet. Then gravity is decidedly not your friend.
That should do it for today. I should be able to post more next week.
Thanks!
HN