https://en.wikipedia.org/wiki/Attrition_warfare
Attrition warfare represents an attempt to grind down an opponent's ability to make war by destroying their military resources by any means including guerrilla warfare, people's war, scorched earth and all kind of battles apart from a decisive battle.[1] Attrition warfare does not include all kinds of Blitzkrieg or using concentration of force and a decisive battle to win. The side that reinforces his army at a higher speed will normally win the war. Clausewitz called it the exhaustion of the adversary.[4]
A side that perceives itself to be at a marked disadvantage may deliberately seek out attrition warfare to neutralize its opponent's advantages over time. Sun Tzu has stated, that there is no country that has benefitted from prolongued warfare,[5] but Russia in 1812 won the war with attrition warfare against Napoleon. When attritional methods have worn down the enemy sufficiently to make other methods feasible, attritional methods are often complemented or even abandoned by other strategies. But in World War I military commanders on both sides relied on attrition warfare resulting in terrible casualties without a strategic result.
The difference between war of attrition and other forms of war is somewhat artificial since even a single battle normally contains an element of attrition. One can be said to pursue a strategy of attrition if one makes it the main goal to cause gradual attrition to the opponent eventually amounting to unacceptable or unsustainable levels for the opponent while limiting one's own gradual losses to acceptable and sustainable levels. That should be seen as opposed to other main goals such as the conquest of some resource or territory or an attempt to cause the enemy great losses in a single stroke (such as by encirclement and capture). Attrition warfare also tries to increase the friction in a war for the opponent.[6]
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