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Deborah Bauer




The Central Intelligence Agency (CIA) involved itself in multiple operations that aimed to contain or prevent the spread of Communism during the twentieth century. The purpose of this project was to examine Operation PBSUCCESS, the CIA’s coup d’etat against Jacobo Arbenz, the democratically elected president in Guatemala in the 1950s. Using declassified documents from the CIA library, as well as scholarly secondary sources on the contemporary situation in Guatemala and on the CIA’s involvement, this project sought to understand how the CIA had determined that Communism infiltrated Guatemala. After careful analyses, I concluded that the CIA misinterpreted their gathered intelligence reports due to confirmation bias, an unconscious process where information is erroneously examined and interpreted to fit with one’s presumptions. The contemporary fear of Communism obscured the CIA’s ability to objectively evaluate Guatemala; the CIA believed there were significantly larger numbers of Communists in the government and voting population than there in fact were. Furthermore, this confirmation bias affected the CIA’s analysis on collaboration between the Soviet Union and Guatemala and on Guatemalan policies. The project concludes that Operation PBSUCCESS can be characterized as a failed intelligence operation due to the misinformation produced from confirmation bias. This conclusion is significant as it is a revisionist interpretation on this operation and how successful it actually was. This is important as it demonstrates the need to be skeptical, even when results turn out favorably.



Operation PBSUCCESS? The CIA and Confirmation Bias in Guatemala

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