It's a well known fact that both USA and USSR had a huge influence on South America during the Cold War, but today I want to share a mostly unknown fact about the consequences.
The CIA aided and trained the right wing military in Brazil because they feared that the left wing president João Goulart since he planned on making alliances with China, in 1964 the army made their move and made a coup thus starting the Military Dictatorship. As the years passed, the military dictatorship got more and more ruthless and in the "Iron Years" of the dictatorship many were tortured and killed accused of having communist ties, a lot of left leaning college teachers were arrested and sent to the Ilha Grande's Prision to live with regular criminals. During their stay, some of these intelectuals decided to teach things like guerrilla warfare and how to organize themselves hoping to make a guerrilla using common criminals, this backfired and the previously uneducated, disorganized became the infamous Red Command, highly trained criminals who now organized themselves and took over the criminal underworld in Rio de Janeiro.
During the military dictatorship, the police were militarized and trained basically like soldiers in order to have more man in a fight versus the communists. That means even 6 years after the end of the dictatorship they were still trained to kill instead of serve and protect, the lack of proper training escalated in the Carandiru massacre where police officers executed more than 100 inmates because of unprofessionalism. This caused a massive outrage in other prisions and the small scattered gangs united as one and founded the PCC (First command of the capital) and soon they gained control of the criminal underworld in Brazil's economic center (São Paulo) including the main cocaine routes to Europe.
Source: reddit post