Final answer:
COINTELPRO was a controversial program created by J. Edgar Hoover to investigate groups that posed a threat, initially targeting the Communist Party of the USA and later expanding to various other organizations.
Step-by-step explanation:
When J. Edgar Hoover investigated groups that posed as a threat, he created a controversial program known as COINTELPRO. Launched in 1956, COINTELPRO (Counter Intelligence Program) was aimed at infiltrating and disrupting the Communist Party of the USA (CPUSA) and later expanded its scope to include surveillance and disruption of a variety of organizations, including the civil rights movement, feminist groups, and environmentalists. This program persisted through various administrations, highlighting the deep fears of communism within the U.S. and the government's response to this perceived threat. It also highlighted the lengths to which the FBI, under Hoover, would go to maintain what it considered national security, including tactics that many criticized as overreaching and illegal.