The CIA spent 45 years and hundreds of billions of dollars tracking every Soviet weapons system, mapping every military base, and recruiting agents inside the Soviet apparatus. When the Soviet Union collapsed on December 25, 1991, the CIA had not predicted it.
As late as 1989, CIA analysis described the Soviet economy as stable. The National Intelligence Estimates systematically overestimated Soviet GDP by a factor of two. Analysts were influenced by what they wanted to find — a strong adversary justified large budgets — and by the theoretical impossibility (in their model) of a Communist economy collapsing from within.
The Aldrich Ames treason compounded the failure: the CIA's best Soviet sources had been burned since 1985. The Agency was operating largely blind inside the Soviet system in its final years. When the coup against Gorbachev came in August 1991, the CIA had 72 hours of warning — barely enough to call the President.
The September 11 attacks were the CIA's second catastrophic intelligence failure in a decade. The Agency had tracked two of the 9/11 hijackers into the United States and failed to notify the FBI. Internal disputes between CIA Counterterrorism Center and FBI counterpart units — a turf war rooted in decades of bureaucratic rivalry — allowed the plot to proceed.
In the aftermath, the CIA launched a global campaign against al-Qaeda that included extraordinary rendition (kidnapping suspected terrorists from third countries and transferring them to CIA "black sites" or cooperative foreign governments for interrogation), enhanced interrogation techniques (what critics and international law call torture: waterboarding, sleep deprivation, stress positions, rectal feeding, confinement in small boxes), and an expanding drone strike program that operated in countries the United States was not at war with.
The Senate Intelligence Committee's 2014 Torture Report — 6,700 pages, of which 525 were eventually released — concluded that enhanced interrogation techniques did not produce intelligence that prevented attacks, that the CIA repeatedly misled Congress about the program's effectiveness, and that the program was "far worse than the CIA represented." No CIA officer was prosecuted. Several were promoted.