The main inspiration for the game is the US War on Drugs.
In 1971, Richard Nixon declared the prevention of drug abuse in the United States a number one priority of the US government. Among the policies enacted as part of the WoD were domestic measures like criminalization of more kinds of drugs, drug prevention programs, more resources spent on fighting domestic drug distribution and detecting drug smuggling operations.
Later administrations then added another approach to the drug problem: attacking the source of the drugs directly. The US started various military operations in Central- and South-America with the goal to destroy the drug production industry and smuggling lines of the drug cartels. The intention was to reduce the amount of drugs available on the world market and thus the amount of drugs smuggled into the United States.
These military operations focused on:
Bolivia was not officially targeted by the US War on Drugs so far, even though it's one of the main cocain producers in the world. That's where the fiction of the game comes in.
However, the "This game is not a representation of the reality of Bolivia" disclaimer at startup should be taken seriously. Even the Bolivian government complained about the gross misrepresentation of Bolivia in the game. That complaint is quite justified, because the game takes a lot of creative freedoms:
- Unidad is fictional. Bolivia has no military branch or law enforcement agency by that name. It might be inspired by Plan Dignidad, a Bolivian drug law enforcement initiative in the 90s. In contrary to the fictional version from the game, it was not immediately undermined by drug cartels. They were quite successful and reduced the Bolivian coca production to a third in just 4 years.
- The Santa Blanca cartel is completely fictional. Small-scale coca farming is partly legal in Bolivia, which makes a monopolistic drug cartel unnecessary.
- Coca production in Bolivia is in fact going down in the past years. The current strategy of the Bolivian government is one of soft pressure. Coca production is still legal, but regulated. The allowed production numbers are gradually reduced to give people working in the coca industry enough time to find other professions.
- The Santa Muerte cult is real, but only exists in Mexico. It's not a part of Bolivian culture.
For more information, check the Wikipedia article on illegal drug trade in Bolivia.