Strategic depth
Strategic depth is a term in military literature that broadly refers to the distances between the front lines or battle sectors and the combatants' industrial core areas, capital cities, heartlands, and other key centers of population or military production.
Concept[edit]
The key precepts any military commander must consider when dealing with strategic depth are how vulnerable these assets are to a quick, preemptive attack or to a methodical offensive and whether a country can withdraw into its own territory, absorb an initial thrust, and allow the subsequent offensive to culminate short of its goal and far from its source of power.
Commanders must be able to plan for both eventualities, and have measures and resources in place on both tactical and strategic levels to counter any and all stages of a minor or major enemy attack. The measures do not need to be limited to purely-military assets since the ability to reinforce civilian infrastructure or make it flexible enough to withstand or evade assault is very useful in times of war. The issue was the tradeoff between space and time as witnessed by Germany’s failure to defeat the Soviet Union in 1942. In the face of a German invasion, the Soviet military retreated from occupied Poland in June 1941 to the outskirts of Moscow in December 1941, which allowed the Soviet Union to move its industrial base to the east of the Ural Mountains. Thus, the industries that had been moved were able to produce the resources that were needed for the Soviet counterattack.