Wave theory refers to the “Four Waves of Modern Terrorism,” which was published in 2004 by David C. Rapoport, professor emeritus at the University of California, Los Angeles, and a founding editor of the journal Terrorism and Political Violence. Wave theory made a unique contribution to the study of terrorism by positing a generational model that linked contemporaneous global terrorist groups based on their shared characteristics of ideology/theology, strategy/tactics, and visions for the future. Although wave theory is focused on the modern period, from the late 19th century to the present day, it is built on a thorough grounding of the history of terrorism, which dates from the 1st century ce.
Since its inception as a separate political entity in 1747, Afghanistan has been embroiled in almost perpetual warfare but has never been ruled directly by the military. From initial expansionist military campaigns to involvement in defensive, civil, and internal consolidation campaigns, the Afghan military until the mid-19th century remained mainly a combination of tribal forces and smaller organized units. The central government, however, was only able to gain tenuous monopoly over the use of violence throughout the country by the end the 19th century. The military as well as the Afghan society remained largely illiterate and generally isolated from the prevailing global political and ideological trends until the middle of the 20th century. The politicization of the Afghan military began in very small numbers after World War II, with Soviet-inspired communism gaining the largest foothold. Officers associated with the People’s Democratic Party of Afghanistan were instrumental in two successful coups d’état in the country. In 1979, the Soviet Union invaded Afghanistan, ending the country’s sovereignty and ushering in a period of conflict that has continued into the third decade of the 21st century in varying degrees. In 2001, the United States led an international invasion of the country, which was followed by efforts to organize smaller, professional Afghan national defense forces, which remained largely apolitical and became the country’s most effective and trusted governmental institution. However, designed by foreign forces to support foreign goals, they disintegrated when left to defend the country independently against the Taliban in 2021. The Taliban may represent a new phenomenon in Afghanistan, that of having a politicized militarized force.