From the Summary: "Colombia--a close U.S. ally in Latin America--endured more than half a century of internal armed conflict. To address the country's role in illegal drug production, the United States and Colombia forged a close relationship. Plan Colombia, a program focused initially on counter-narcotics and later on counterterrorism, laid the foundation for an enduring security partnership that has lasted more than two decades. The United States also has supported the implementation of a peace accord that President Juan Manuel Santos (2010-2018) concluded with the Revolutionary Armed Forces of Colombia (FARC)--the country's largest leftist guerrilla organization at the time."
CRS Report for Congress, R43813
Congressional Research Service: https://crsreports.congress.gov/