Interior lines

Interior lines is a strategy of warfare that is based on the concept that lines of movement, communication, and supply within an area are shorter than those on the outside or exist on the inside exclusively. As the area held by a defensive force shrinks, the advantages increase.

Using the strategy of interior lines, a surrounded force can more easily supply, communicate, and move its forces around, and it can mount a series of quick attacks on the forces encircling it.

In the context of battle field tactics, it allows for the greater concentration of resources at a greater rate then an adversary can. That allows for higher concentrations of resources, firepower and manpower than an adversary can and so affords greater tactical flexibility. The resources are presumably employed against an adversary in a way to which they are not prepared to respond. The tactic simultaneously ensures a slower concentration of similar resources at a given point by an adversary:

As a strategy, it is commonly employed to cut armies off from reinforcements supplies, or prevent allies from uniting their forces. That usually allows for an adversary that may not be numerically superior to gain a numerical superiority over an adversary in a given locality, which increases the chances of overpowering an enemy and defeating it. By extension, in overpowering an enemy, an adversary hopes to demoralize it to a sufficient degree to bring it to political terms.

Examples

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