https://en.prolewiki.org/wiki/Central_Intelligence_Agency#Blowback

“Blowback” is a CIA term first used in March 1954 in a now declassified report on the 1953 operation to overthrow the government of Mohammed Mossadegh in Iran. It is a metaphor for the unintended consequences of the US government’s international activities that have been kept secret from the U.S. public.[30]

One example of blowback is the CIA's financing and support for the Mujahideen to fight an anti-Communist proxy guerrilla war against the USSR in Afghanistan. The Mujahideen would later become Al Qaeda which would commit the September 11, 2001 attacks.

Due to the CIA's function as an anti-communist organization, it typically relies on right-wing groups to achieve its policy goals, either by latching on to and supporting pre-existing anti-communist groups and leaders or helping to create them. This leads to the spread of fascism, terrorism, and increased instability in regions where the CIA has used their influence, even after the CIA has ceased actively using them to achieve specific goals.