Abstract This essay provides an analysis of the Jemaah Islamiyah terrorist group from its founding and grassroots development until the group's split in 2000. It also provides an analysis of the motivations behind its founder and the future of JI and radical Islam. The analysis is provided in seven parts that cover key areas including the establishment of the JI, the status and role of Ba'asyir, the ideological influence of Darul Islam, the manifesto and operational charter of the JI, the The breakup of the JI and the future of Islamic extremists and the response of the authorities. The analysis shows that Islamic extremism is not only present but widespread in Indonesia today. Radical groups like JI and the recently identified Aceh cell are actively planning to carry out mass casualty attacks against civilians and high-ranking political figures, including the use of suicide bombings, in the name of Islam. Terrorists in Indonesia have carried out some of the bloodiest attacks. recent times. Their casualty record is high and they are responsible for the deaths of hundreds of innocent civilians, targeted because they were infidels or Westerners. In conclusion, it is evident that Islamic extremist groups will continue to carry out acts of terror in pursuit of their persistent goals and attempts. to impose power over the population under Sharia law. Ba'asyir's influence will continue to be a driving force of motivation and spirituality for radical organizations and individuals for the foreseeable future, regardless of their incarceration, release, or execution. The persistent efforts of Indonesian authorities and regional partners to combat religious extremism are not only imperative, but essential. The analysis carried out has limitations, notably the ...... middle of the article ...... Volume III, Number 8, pp. 1Symonds. P, “The political origins of Jemaah Islamiyah: behind the Bali attacks”, Center for Globalization Research, part 1. Accessed 04/08/10 http://www.globalresearch.ca/index.php?context= va&aid=1030Teslik . L, “Profile: Abu Bakar Bashir”, Council on Foreign Relations, June 2006. Accessed 05/08/10 http://www.cfr.org/publication/10219/profile.htmlThe Associated Press, “Key dates of the modern politics of Indonesia. history', Associated Press Newswires, 2004, pp. 5Vaughn, B, 'Terrorism in Southeast Asia', Congressional Research Service, October 16, 2009, pp. 5Van Bruinessen, M, 'Genealogies of Islamic Radicalism in Post-Suharto Indonesia', Southeast Asia Research, 2004, pp. 31 Vaswani. K, “Indonesian cleric Abu Bakar Ba'asyir arrested on terrorism charges”, BBC News. Recovered 10/08/10