A war between belligerents whose relative military power differs significantly
Asymmetric warfare (or asymmetric engagement) is a type of war between belligerents whose relative military power, strategy or tactics differ significantly. This type of warfare often, but not necessarily, involves insurgents, terrorist groups, or resistance militias operating within territory mostly controlled by the superior force.
"Asymmetrical warfare" can also describe a conflict in which belligerents' resources are uneven, and consequently, they both may attempt to exploit each other's relative weaknesses. Such struggles often involve unconventional warfare, with the weaker side attempting to use strategy to offset deficiencies in the quantity or quality of their forces and equipment. Such strategies may not necessarily be militarized. This is in contrast to "symmetrical warfare", where two powers have comparable military power, resources, and rely on similar tactics.
Asymmetric warfare is a form of irregular warfare – conflicts in which enemy combatants are not regular military forces of nation-states. The term is frequently used to describe what is also called "guerrilla warfare", "insurgency", "counterinsurgency", "rebellion", "terrorism", and "counterterrorism".
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Definition and differences.
The popularity of the term dates from Andrew J. R. Mack's 1975 article "Why Big Nations Lose Small Wars" in "World Politics", in which "asymmetric" referred simply to a significant disparity in power between opposing actors in a conflict. "Power," in this sense, is broadly understood to mean material power, such as a large army, sophisticated weapons, an advanced economy, and so on. Mack's analysis was largely ignored in its day, but the end of the Cold War sparked renewed interest among academics. By the late 1990s, new research building off Mack's works was beginning to mature; after 9/11, the U.S. military began once again to grapple with asymmetric warfare strategy.
Since 2004, the discussion of asymmetric warfare has been complicated by the tendency of academic and military officials to use the term in different ways, as well as by its close association with guerrilla warfare, insurgency, terrorism, counterinsurgency, and counterterrorism.
Academic authors tend to focus on explaining two puzzles in asymmetric conflict. First, if "power" determines victory, there must be reasons why weaker actors decide to fight more powerful actors. Key explanations include:
Second, if "power," as generally understood, leads to victory in war, then there must be an explanation for why the "weak" can defeat the "strong." Key explanations include:
Asymmetric conflicts include interstate and civil wars, and over the past two hundred years, have generally been won by strong actors. Since 1950, however, weak actors have won the majority of asymmetric conflicts. In asymmetric conflicts conflict escalation can be rational for one side.
Strategic basis.
In most conventional warfare, the belligerents deploy forces of a similar type, and the outcome can be predicted by the quantity or quality of the opposing forces, for example, better command and control of theirs (c2). There are times when this is the case, and conventional forces are not easily compared, making it difficult for opposing sides to engage. An example of this is the standoff between the continental land forces of the French Army and the maritime forces of the United Kingdom's Royal Navy during the French Revolutionary and Napoleonic Wars. In the words of Admiral Jervis during the campaigns of 1801, "I do not say, my Lords, that the French will not come. I say only they will not come by sea", and a confrontation that Napoleon Bonaparte described as that between the elephant and the whale.
Tactical basis.
The tactical success of asymmetric warfare is dependent on at least some of the following assumptions:
Terrorism.
There are two opposing viewpoints on the relationship between asymmetric warfare and terrorism. In the modern context, asymmetric warfare is increasingly considered a component of fourth generation warfare. When practiced outside the laws of war, it is often defined as terrorism, though rarely by its practitioners or their supporters. The other view is that asymmetric warfare does not coincide with terrorism.
Use of terrain.
Terrain that limits mobility, such as forests and mountains, can be used as a force multiplier by the smaller force and as a force inhibitor against the larger one, especially one operating far from its logistical base. Such terrain is called "difficult terrain". Urban areas, though generally having good transport access, provide innumerable ready-made defensible positions with simple escape routes and can also become rough terrain if prolonged combat fills the streets with rubble:
 ;templatestyles src="Template:Blockquote/styles.css" / ;The contour of the land is an aid to the army, sizing up opponents to determine victory and assessing dangers and distance. "Those who do battle without knowing these will lose."
 ;templatestyles src="Template:Blockquote/styles.css" / ;The guerrillas must move amongst the people as a fish swims in the sea.
In the 12th century, irregulars known as the Assassins were successful in the Nizari Ismaili state. The "state" consisted of fortresses (such as the Alamut Castle) built on strategic mountaintops and highlands with difficult access, surrounded by hostile lands. The Assassins developed tactics to eliminate high-value targets, threatening their security, including the Crusaders.
In the American Revolutionary War, Patriot Lieutenant Colonel Francis Marion, known as the "Swamp Fox," took advantage of irregular tactics, interior lines, and the wilderness of colonial South Carolina to hinder larger British regular forces.
Yugoslav Partisans, starting as small detachments around mountain villages in 1941, fought the German and other Axis occupation forces, successfully taking advantage of the rough terrain to survive despite their small numbers. Over the next four years, they slowly forced their enemies back, recovering population centers and resources, eventually growing into the regular Yugoslav Army.
The Vietnam war is a classical example of the use of terrain to fight an asymmetrical war, The North Vietnamese army (NVA) and Viet Cong (VC) used the dense jungles, mountains, and river systems of Vietnam to allow for effective concealment of troop movements in spite of superior enemy air power. This allowed supplying troops to be possible without incurring heavy losses from American airstrikes, who could not effectively identify or track their movements from the air. This was true to such an extent that the US employed defoliation methods such as the use of Agent Orange and extensive Napalm use to make forested areas visible from the air. The NVA and VC also used intricate tunnel systems, such as the Củ Chi tunnels, which enabled them to move undetected, store supplies, and evade U.S. search-and-destroy missions.
Role of civilians.
Civilians can play a vital role in determining the outcome of an asymmetric war. In such conflicts, when it is easy for insurgents to assimilate into the population quickly after an attack, tips on the timing or location of insurgent activity can severely undermine the resistance. An information-central framework, in which civilians are seen primarily as sources of strategic information rather than resources, provides a paradigm to understand better the dynamics of such conflicts where civilian information-sharing is vital. The framework assumes that:
Given the additional assumption that the larger or dominant force is the government, the framework suggests the following implications:
A survey of the empirical literature on conflict, does not provide conclusive evidence on the claims. But the framework gives a starting point to explore the role of civilian information sharing in asymmetric warfare.
War by proxy.
Where asymmetric warfare is carried out (generally covertly) by allegedly non-governmental actors who are connected to or sympathetic to a particular nation's (the "state actor's") interest, it may be deemed "war by proxy." This is typically done to give the state actor "deniability". The deniability can be crucial to keep the state actor from being tainted by the actions, to allow the state actor to negotiate in apparent good faith by claiming they are not responsible for the actions of parties who are merely sympathizers, or to avoid being accused of belligerent actions or war crimes. If proof emerges of the true extent of the state actor's involvement, this strategy can backfire; for example, see Iran-contra and Philip Agee.
Examples.
American Indian Wars.
Benjamin Church designed his force primarily to emulate Native American patterns of war. Toward this end, Church endeavored to learn to fight like Native Americans from Native Americans. Americans became rangers exclusively under the tutelage of the Native American allies. (Until the end of the colonial period, rangers depended on Native Americans as both allies and teachers.)
Church developed a special full-time unit mixing white colonists selected for frontier skills with friendly Native Americans to carry out offensive strikes against hostile Native Americans in terrain where normal militia units were ineffective. Church paid special care to outfitting, supplying and instructing his troops in ways inspired by indigenous methods of warfare and ways of living. He emphasized the adoption of indigenous techniques, which prioritized small, mobile and flexible units which used the countryside for cover, in lieu of massed frontal assaults by large formations. Benjamin Church is sometimes referred to as the father of Unconventional warfare. 
American Revolutionary War.
From its initiation, the American Revolutionary War was, necessarily, a showcase for asymmetric techniques. In the 1920s, Harold Murdock of Boston attempted to solve the puzzle of the first shots fired on Lexington Green and came to the suspicion that the few score militiamen who gathered before sunrise to await the arrival of hundreds of well-prepared British soldiers were sent to provoke an incident which could be used for Patriot propaganda purposes. The return of the British force to Boston following the search operations at Concord was subject to constant skirmishing by Patriot forces gathered from communities all along the route, making maximum use of the terrain (particularly, trees and stone field walls) to overcome the limitations of their weapons – muskets with an effective range of only about 50–70 meters. Throughout the war, skirmishing tactics against British troops on the move continued to be a key factor in the Patriots' success; particularly in the Western theater of the American Revolutionary War.
Another feature of the long march from Concord was the urban warfare technique of using buildings along the route as additional cover for snipers. When revolutionary forces forced their way into Norfolk, Virginia and used waterfront buildings as cover for shots at British vessels out in the river, the response of destruction of those buildings was ingeniously used to the advantage of the rebels, who encouraged the spread of fire throughout the largely Loyalist town and spread propaganda blaming it on the British. Shortly afterwards, they destroyed the remaining houses because they might provide cover for British soldiers.
The rebels also adopted a form of asymmetric sea warfare by using small, fast vessels to avoid the Royal Navy and capturing or sinking large numbers of merchant ships; however the Crown responded by issuing letters of marque permitting private armed vessels to undertake similar attacks on Patriot shipping. John Paul Jones became notorious in Britain for his expedition from France in the sloop of war "Ranger" in April 1778, during which, in addition to his attacks on merchant shipping, he made two landings on British soil. The effect of these raids, particularly when coupled with his capture of the Royal Navy's – the first such success in British waters, but not Jones' last – was to force the British government to increase resources for coastal defense, and to create a climate of fear among the British public which was subsequently fed by press reports of his preparations for the 1779 "Bonhomme Richard" mission.
From 1776, the conflict turned increasingly into a proxy war on behalf of France, following a strategy proposed in the 1760s but initially resisted by the idealistic young King Louis XVI, who came to the throne at the age of 19 a few months before Lexington. France ultimately drove Great Britain to the brink of defeat by entering the war(s) directly on several fronts throughout the world.
American Civil War.
The American Civil War saw the rise of asymmetric warfare in the Border States, and in particular on the US Western Territorial Border after the Kansas-Nebraska Act of 1854 opened the territories to vote on the expansion of slavery beyond the Missouri Compromise lines. Political implications of this broken 1820's compromise were nothing less than the potential expansion of slavery all across the North American continent, including the northern reaches of the annexed Mexican territories to California and Oregon. So the stakes were high, and it caused a flood of immigration to the border: some to grab land and expand slavery west, others to grab land and vote down the expansion