The United States manages to spread its tentacles into different countries around the world in various ways, influencing and intervening in the politics of sovereign nations. In Latin America, one of the most common ways is through supposed "drug operations." The CIA has been known to run "anti-drug" operations in countries like Bolivia, Colombia and Ecuador.
In Venezuela, such CIA-created "anti-drug" operations were led in the 1980's by the same General Ramon Guillén Dávila who was recently planning to kill Chávez. According to the Miami Herald, Guillen was the CIA's most trusted man in Venezuela and the senior official collaborating with the CIA during the 1980's.
As head of the Venezuela National Guard, Guillén worked closely with the CIA to infiltrate and gather information about Colombian drug trafficking operations. But instead of curbing drug operations, Guillén and the CIA ended up smuggling cocaine themselves, and the whole thing exploded when 60 Minutes aired an expose in 1993. The CIA had collaborated with Guillén to smuggle the incredible sum of 22 tons of cocaine into the United States.
After US customs intercepted a shipment of cocaine entering the country through Miami Internatoinal Airport, an official investigation revealed that General Guillén was responsible. But according to investigative journalist Michael Levine, Guillén was a CIA "asset" operating under CIA orders and protection, a fact that was later admitted by the CIA. General Guillén was never extradited for trial in the U.S.
So is General Ramon Guillén Dávila still a CIA "asset" working to knock off the Venezuelan President? Whether or not the General maintains ties with the CIA, it does seem that he would be a likely candidate for destabilization efforts against the Chávez government.
According to the web page School of the Americas Watch, General Guillén graduated from the infamous U.S. combat training school in 1967.  The School of the Americas, renamed the Western Hemisphere Institute for Security Cooperation in 2001, is a US military facility that is used to train Latin American soldiers in counterinsurgency techniques and interrogation tactics.
From: Is The CIA Trying to Kill Hugo Chávez? By Chris Carlson