Total war is a neologism to describe an international war in which countries or nations use all of their resources to destroy another organized country's or nation's ability to engage in war. The practice of total war has been in use for centuries, but it was only in the middle to late nineteenth century that total war was recognized as a separate class of warfare. Total war is most easily distinguished from other forms of warfare through a blurring and combining of strategy and grand strategy.
There are several reasons for changing concept and recognition of total war in the nineteenth century. The main reason is industrialization. As countries natural and capital resources grew, it became clear that some forms of conflict demanded more resources than others. For example, if the United States was to subdue a Native American tribe in an extended campaign lasting years, it still took much fewer resources than waging a month of war during the American Civil War. Consequently, the greater cost of warfare became evident. An industrialized nation could distinguish and then choose the intensity of warfare that it wished to engage in.
This is also the same time when nations were fighting colonial wars. A country such as Britain would have no need to mobilize troops, or begin rationing at home when fighting a native enemy in Africa. But when Britain was fighting in the First World War (note that this was not necessarily a fight for her life), a different form of warfare was needed. As such, strategies (in the generic sense) needed to adapt to this new grand strategy.
Additionally, this is the time when warfare was becoming more mechanized. A factory in a city would have more to do with warfare than it did before. The factory itself would become a target, because it contributed to the war effort. It follows as well that the factory's workers would also be targets.
The most identifiable consequence of total war in modern times has been the inclusion of civilians as targets in destroying a country's ability to engage in war. The targeting of civilians developed from two distinct theories. The first theory was that if enough civilians were killed, factories could not function. The second theory was that if civilians were killed, the country would be so demoralized that it would have no ability to wage further war.
Total war also resulted in the mobilization of the so called home front. Propaganda became a required component of total war in order to boost production and maintain morale. Rationing took place to provide more material for waging war.
Another consequence was the expansion of the military. Because wars were no longer local affairs, soldiers had to be deployed globally. Additionally, a navy could not be built overnight, and it had to be prepared for warfare. Standing armies and strong navies were the only way to ensure victories or prevent defeats before the economy could be mobilized.
The final consequence of total war eventually became, ironically, an end to war between industrialized nations. After World War II, industrialized nations' ability to wage war between each other became terribly destructive, and at the end of the 1950s, resulting in the development of MAD (Mutually Assured Destruction). With nuclear weapons, the conclusion of total war became something that instead of taking years, such as in World War I, would instead take hours. Essentially, the consequences of total war became so terrible for both sides in the conflict that no clear economic winner could emerge. The economic impetus for open war directly between industrialized nations had ended.
Instead of wars fought directly between world powers, wars between industrialized nations were fought by proxy over national prestige, tactical strategic advantage or colonial and neocolonial resources. Examples include the US war in Vietnam, the Six Day War, and the Soviet War in Afghanistan.
Punic Wars. During the Punic Wars, Rome and Carthage fought with navies and armies across several theatres. In the end, Rome destroyed the city-state of Carthage, and destroying the empire's ability to wage war by enslaving or committing genocide on the Carthaginian populace.
US Army General William Tecumseh Sherman's 'March to the Sea' during the American Civil War and his campaigns against Native Americans both destroyed the resources required for the South to make war. He is considered one of the first military commanders to use total war as a military tactic.
World War I. Almost the whole of Europe mobilized to conduct the war. Young men were removed from production jobs, and were replaced by women. Rationing occurred on the home fronts.
World War II. In the Second World War, Britain and Germany made a distinct attempt to destroy the other's ability to produce war materials. They did this by the use of strategic bombing campaigns upon each others' cities at night. Total war was also used in battles between Nazi Germany and Soviet Russia, where both sides committed huge numbers of troops and weapons against one another and against civilians.