furthermore loyalist paramilitaries such as the Glenanne gang included serving members of the Ulster Defense Regiment and Royal Ulster Constabulary. Guerrilla warfare: the main challenge to low-intensity warfare Low-intensity warfare's main opponent is the guerrilla, or irregular fighter. This opponent may be state sponsored, or private non-state actors driven by religious or other ideology in urban, semi-urban and rural areas. Modern guerrilla warfare at its fullest elaboration is an integrated process, complete with sophisticated doctrine, organization, specialist skills and propaganda capabilities. Guerrillas can operate as small, scattered bands of raiders, but they can also work side by side with regular forces or combine for far-ranging mobile operations in squad, platoon or battalion sizes or even form conventional units. Based on their level of sophistication and organization, they can shift between all those modes as the situation demands, as guerrilla warfare is flexible, not static. Guerrilla tactics are based on intelligence, ambush, deception, sabotage, and espionage, undermining an authority by long, low-intensity confrontation. It can be quite successful against an unpopular foreign or local regime, as demonstrated by the Vietnam War. A guerrilla army may increase the cost of maintaining an occupation or a colonial presence above what the foreign power may wish to bear. Against a local regime, guerrillas may make governance impossible by terror strikes and sabotage or even a combination of forces to depose their local enemies in conventional battle. Those tactics are useful in demoralizing an enemy and raising the morale of the guerrillas. In many cases, guerrilla tactics allow a small force to hold off a much larger and better equipped enemy for a long time, as in Russia's Second Chechen War and the Second Seminole War fought in the swamps of Florida, United States. Guerrilla tactics and strategy are summarized below and are discussed extensively in standard reference works such as Mao's On Guerrilla Warfare. Three-phase Maoist model Mao/Giap approach Mao's theory of people's war divides warfare into three phases. In the first phase, the guerrillas gain the support of the population by attacking the machinery of government and distributing propaganda. In the second phase, escalating attacks are made on the government's military and vital institutions. In the third phase, conventional fighting is used to seize cities, overthrow the government, and take control of the country. Mao's seminal work On Guerrilla Warfare, has been widely distributed and applied, nowhere more successfully than in Vietnam, under