Theodore John Kaczynski (; born May 22, 1942), also known as the Unabomber (), is an American domestic terrorist, former mathematics professor, and anarchist author. A mathematics prodigy, he abandoned an academic career in 1969 to pursue a primitive lifestyle. Between 1978 and 1995, he killed three people and injured 23 others in an attempt to start a revolution by conducting a nationwide bombing campaign targeting people involved with modern technology. In conjunction, he issued a social critique opposing industrialization while advocating a nature-centered form of anarchism.
In 1971, Kaczynski moved to a remote cabin without electricity or running water near Lincoln, Montana, where he lived as a recluse while learning survival skills in an attempt to become self-sufficient. After witnessing the destruction of the wilderness surrounding his cabin, he concluded that living in nature was untenable and began his bombing campaign in 1978. In 1995, he sent a letter to The New York Times and promised to "desist from terrorism" if The Times or The Washington Post published his essay, Industrial Society and Its Future, in which he argued that his bombings were extreme but necessary to attract attention to the erosion of human freedom and dignity by modern technologies that require large-scale organization.
Kaczynski was the subject of the longest and most expensive investigation in the history of the Federal Bureau of Investigation (FBI). Before his identity was known, the FBI used the acronym UNABOM (University and Airline Bomber) to refer to his case, which resulted in the media naming him the "Unabomber". The FBI and Attorney General Janet Reno pushed for the publication of Industrial Society and Its Future, which led to a tip-off from Kaczynski's brother, David Kaczynski, who recognized the writing style.
After his arrest in 1996, Kaczynski tried unsuccessfully to dismiss his court-appointed lawyers because they wanted him to plead insanity in order to avoid the death penalty, as he did not believe he was insane. In 1998 a plea bargain was reached, under which he plead guilty to all charges and was sentenced to life in prison without the possibility of parole.