warfare, violent conflict between armed enemies. In modern times warfare has usually been conducted by the armed forces (e.g., army, navy, and air force) of a nation or other politically organized group. The way in which war is carried out is governed by the principles of strategy and tactics, by the type of weapons employed (see articles on individual weapons), and by the type of communication and transportation facilities available. Thus, throughout history the methods of warfare have changed. See air forces; amphibious warfare; chemical warfare; biological warfare; fortification; mechanized warfare; trench warfare; guerrilla warfare; siege.

Warfare in which the opposing sides attack, counterattack, and defend from sets of trenches dug into the ground. It was developed by Sébastien Le Prestre de Vauban in the 17th century for laying siege to fortresses. Its defensive use was first institutionalized as a tactic during the American Civil War. It reached its highest development in World War I. Little used in World War II, it reappeared in the Iran-Iraq War in the 1980s. A typical construction consisted of two to four parallel trenches, each dug in a zigzag, protected by sandbags, and floored with wooden planks. The parallel trenches were connected by a series of communication trenches dug roughly perpendicular to them. The first row was fronted by barbed wire and contained machine-gun emplacements; the rear trenches housed most of the troops. Increased use of tanks marked the end of trench warfare, since tanks were invulnerable to the machine-gun and rifle fire used by entrenched soldiers.

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Use of propaganda against an enemy, supported by whatever military, economic, or political measures are required, and usually intended to demoralize an enemy or to win it over to a different point of view. It has been carried on since ancient times. The conquests of Genghis Khan were aided by expertly planted rumours about large numbers of ferocious Mongol horsemen in his army. Specialized units were a major part of the German and Allied forces in World War II and the U.S. armed forces in the Korean and Vietnam wars. Strategic psychological warfare is mass communications directed to a very large audience or over a considerable expanse of territory; tactical psychological warfare implies a direct connection with combat operations (e.g., the surrender demand). Consolidation psychological warfare consists of messages distributed to the rear of one's own advancing forces for the sake of protecting the line of communications, establishing military government, and carrying out administrative tasks within such a government.

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Military operations conducted on, under, or over the sea and waged against other seagoing vessels or targets on land or in the air. The earliest naval attacks were raids by the armed men of a tribe or town using fishing boats or merchant ships. The first warships were galleys, replaced in the 16th and 17th centuries by sail-driven warships equipped with cannons. The British victory over the Spanish Armada (1588) marked a major development: British galleons refused to allow the Spanish ships to get close enough for boarding and hand-to-hand combat and instead pounded them with guns of superior firing capability. Ships of the line and cruisers emerged in the 17th and 18th centuries. In the later 19th century, steam replaced sail propulsion, and ironclads offered greater protection against the increasing power of guns. The battleship, developed in these years, reigned until World War II, when the Pearl Harbor attack proved that bombers launched from aircraft carriers could sink any and all surface ships. Since then, naval air power—missiles as well as carrier-based planes—has been the primary weapon of the world's fleets. Submarines also play a major role in naval warfare.

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Use of economic measures by governments engaged in international conflict. These may include export and import controls, shipping controls, trade agreements with neutral nations, and so on. Economic warfare among belligerents began with the blockade and interception of contraband. In World War II it was broadened to include economic pressure applied to neutral countries from which the enemy obtained its supplies. In the Cold War it often involved using measures such as an embargo to deny potential enemies goods that might contribute to their war-making ability.

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Use of lethal or incapacitating chemical weapons in war, and the methods of combating such agents. Chemical weapons include choking agents such as the chlorine and phosgene gas employed first by the Germans and later by the Allies in World War I; blood agents such as hydrogen cyanide or cyanogen gas, which block red blood cells from taking up oxygen; blister agents such as sulfur gas and Lewisite, also dispensed as a gas, which burn and blister the skin; and nerve agents such as Tabun, Sarin, Soman, and VX, which block the transmission of nerve impulses to the muscles, heart, and diaphragm. The horrific casualties suffered in World War I led to the 1925 Geneva Protocol, which made it illegal to employ chemical weapons but did not ban their production. Chemical weapons were used a number of times afterward, most notably by Italy in Ethiopia (1935–36), by Japan in China (1938–42), by Egypt in Yemen (1966–67), and by Iran and Iraq against each other (1984–88). During the Cold War the Soviet Union and U.S. built up enormous chemical arsenals; these were dismantled under the terms of the 1993 Chemical Weapons Convention, which prohibits all development, production, acquisition, stockpiling, or transfer of such weapons. Not all countries have signed the convention, and many are suspected of pursuing clandestine chemical programs. Many military forces have adopted various defensive measures, including chemical sensors, protective garments and gas masks, decontaminants, and injectable antidotes, and some have reserved the option of retaliating in kind to any chemical attack. In 1995 a religious cult killed 12 civilians and injured thousands more with Sarin gas in Tokyo; this pointed out the power of chemical agents as weapons of terror as well as the difficulty of protecting civilian populations. Seealso biological warfare.

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or germ warfare

Military use of disease-producing or poisonous agents, and the means for defending against such agents. Biological warfare agents include many bacteria, such as those which cause anthrax, brucellosis, and typhus; viruses that cause diseases such as equine encephalitis; fungi such as rice blast, cereal rust, wheat smut, and potato blight; and toxins such as botulinum and ricin that are extracted from living organisms. Biological warfare dates from ancient times when warring groups would try to poison enemy soldiers with rotting or diseased corpses, infect cattle and horses, or spread contagion through civilian populations. Following the horrors of World War I, a 1925 Geneva Protocol prohibited the use of biological agents in warfare; however, this did not prevent Japan from using them in China during World War II. During the Cold War the Soviet Union as well as the U.S. and its allies built huge stockpiles of biological agents. Both sides signed the 1972 Biological Weapons Convention, which prohibits the production, stockpiling, or development of biological weapons and requires the destruction of existing stockpiles, but the Soviets conducted a clandestine program until the 1990s. Biological weapons programs can be concealed easily, and the 1972 convention contains no provisions for inspection and reporting. As a result, many states have been suspected of developing biological warfare agents, and some modern armed forces have prepared defensive measures. These include battlefield sensors, protective garments and masks, sterilizing agents, and vaccines.

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Military operations directed against hostile shores and characterized by attacks launched from the sea by naval and landing forces. It has been conducted since ancient times. The Greeks attacking Troy (1200 BC) had to make a shore landing, as did the Persian invaders of Greece prior to the Battle of Marathon (490 BC). The British-led landings at Gallipoli (1915) were the main amphibious assault in World War I. The Allies of World War II found amphibious tactics essential in the island-hopping Pacific campaign and in the famous D-Day of the Normandy campaign, which still ranks as the greatest amphibious assault in history. Amphibious warfare's greatest advantage is its mobility and flexibility; its greatest limitation is that the attacker must start from nothing to build up strength ashore. Modern amphibious forces attempt to overcome this by fielding larger and more efficient landing vessels and also by using helicopters and short-takeoff and -landing airplanes to deploy troops beyond the hostile shore.

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Military operations conducted by airplanes, helicopters, or other aircraft against aircraft or targets on the ground and in the water. Air warfare did not become important until World War I (1914–18). The British, French, German, Russian, and Italian armed forces had flying units, including biplanes armed with machine guns for “dogfights” with enemy fighter aircraft. Zeppelins and larger airplanes carried out bombing raids. The 1920s and '30s saw the development of the monoplane, the all-metal fuselage, and the aircraft carrier. During World War II (1939–45), the Battle of Britain was the first fought exclusively in the air, the Battle of the Coral Sea was the first between carrier-based aircraft, and the atomic bombings of Hiroshima and Nagasaki were the first use of nuclear-armed bombers. In the jet age, air power has continued to be used in strategic bombing of an enemy's home territory (as in the Vietnam War, 1965–74), destroying enemy air forces (as in the Arab-Israeli wars), attacking and defending carrier-based naval fleets (as in the Falkland Islands War, 1982), and supporting ground forces (as in the Persian Gulf War, 1990–91).

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Warfare refers to the conduct of conflict between opponents, and usually involves escalation of aggression from the proverbial "war of words" between politicians and diplomats to full-scale armed conflicts, waged until one side accepts defeat or peace terms are agreed on. Warfare between groups, and even more so between military organisations, require a degree of planning and application of military strategy to be conducted effectively in reaching their stated or assumed objectives and goals.

Warfare by other means

A commitment of any given society to a conflict invariably involves methods of warfare that stop short of those requiring direct armed confrontations, but which nevertheless inflict damage to the opponent society by affecting its motivation to resist, or its standard of living. Usually this is exhibited by affecting the economy of the opponent, one example from the 20th century being the imposition of economic sanctions, or the effect on the morale of the opponent by commitment of the society as a whole to the conflict.

• Economic warfare
• Total war

Military operations marked by a specific characteristic

One to categorize warfare is by differentiation between conventional versus unconventional, where conventional warfare involves well-identified, armed forces fighting one another in a relatively open and straightforward way without weapons of mass destruction. "Unconventional" refers to other types of war which can involve raiding, guerrilla, insurgency, and terrorist tactics or alternatively can include nuclear, chemical, biological warfare or using propaganda with pressure groups to invoke certain feelings much like August Keim did in Wilhelmine Germany.

All of these categories usually fall into one of two broader categories: High intensity and low intensity warfare. High intensity warfare is between two superpowers or large countries fighting for political reasons. Low intensity warfare involves counterinsurgency, guerilla warfare and specialized types of troops fighting revolutionaries.

• Asymmetric warfare
• Conventional warfare
• Chemical warfare
• Guerilla warfare
• Unconventional warfare

Environment as a factor

The environment, and particularly the prevailing terrain and climatic conditions in the area of operations, have always influenced the use of armed forces, including the doctrines, weapon and logistic technologies employed.

Terrain-based warfare factors

Largely related to the geographic location the following types of warfare refer to special consideration of combat in conditions other than those of a temperate climate of European regions.

• Arctic warfare
• Desert warfare
• Jungle warfare
• Mountain warfare

Human-based warfare factors

Some combat operations are influenced by the effect of human actions on the environment, in either modifying it, or affecting the normal functioning of the enemy troops under combat conditions.

• Urban warfare
• Trench warfare
• Psychological warfare

Technology-based warfare factors

As a result of advances in technologies, armed forces have been able to conduct combat by enhancing basic abilities of human participants using technology as a combat multiplier to the basic combat value of an individual combatant. All of the types of warfare below are conducted in environments completely, and are only possible due to use of technology. All are used to increase the tempo, the speed or pace of combat.

• Mobile warfare
• Naval warfare
• Sub-aquatic warfare
• Air warfare
• Electronic warfare
• Cyber warfare
• Space warfare

Historical periods of warfare

Historians have found it useful to differentiate between distinct periods of warfare in history, often as a result of recorded dramatic changes in the conduct of combat due to the influence of technology or changes in the societies that waged wars. Because European technology has dominated warfare since the end of the Renaissance, the periodisation has been largely Eurocentric and technology-oriented.

• Prehistoric warfare - largely speculative unrecorded period
• Ancient warfare - earliest record of human conflicts
• Medieval warfare - first organised warfare in Europe
• Gunpowder warfare - the dramatic shift to scientific warfare
• Industrial warfare - the coupling of new methods of production with support of military operations
• Modern warfare - the increased competition by the militaries in technological sophistication, particularly since the Second World War

See also

• Point d'appui
• War

References

Sources

• Dunnigan, James F., How to make war: A comprehensive guide to modern warfare, Arms & Armour Press, Melbourne, 1982 ISBN 0853685398