The Contras were an anti-Communist organization in Nicaragua. Their tactics involved the destruction of civilian areas. The United States sent them funds until their deadly activities were discovered. Not long after, the Iran-Contra affair occurred, in which the Reagan Administration sold weapons to Iran and paid the Contras with the funds from the sales. However, the sales were discovered, and the people involved, particularly Oliver North, were tried and acquitted for their involvement. The Contras disbanded in 1990 after the failed election of their rivals, the Sandanistas.
The United States began to support Contra activities against the Sandinista government by December 1981, with the CIA at the forefront of operations. The CIA supplied the funds and the equipment, coordinated training programs, and provided intelligence and target lists. While the Contras had little military successes, they did prove adept at carrying out CIA guerrilla warfare strategies from training manuals which advised them to incite mob violence, "neutralize" civilian leaders and government officials and attack "soft targets" — including schools, health clinics and cooperatives. The agency added to the Contras' sabotage efforts by blowing up refineries and pipelines, and mining ports. Finally, according to former Contra leader Edgar Chamorro, CIA trainers also gave Contra soldiers large knives. "A commando knife [was given], and our people, everybody wanted to have a knife like that, to kill people, to cut their throats"
The CIA officer in charge of the covert war, Duane "Dewey" Clarridge, admitted to the House Intelligence Committee staff in a secret briefing in 1984 that the Contras were routinely murdering "civilians and Sandinista officials in the provinces, as well as heads of cooperatives, nurses, doctors and judges". But he claimed that this did not violate President Reagan's executive order prohibiting assassinations because the agency defined it as just 'killing'. "After all, this is war—a paramilitary operation," Clarridge said in conclusion. Edgar Chamorro explained the rationale behind this to a U.S. reporter. "Sometimes terror is very productive. This is the policy, to keep putting pressure until the people cry 'uncle'".The CIA manual for the Contras, Tayacan, states that the Contras should gather the local population for a public tribunal to "shame, ridicule and humiliate" Sandinista officials to "reduce their influence". It also recommends gathering the local population to witness and take part in public executions. These types of activities continued throughout the war. After the signing of the Central American Peace Accord in August 1987, the year war related deaths and economic destruction reached its peak, the Contras eventually entered negotiations with the Sandinista government (1988), and the war began to deescalate.
By 1989 the US backed Contra war and economic isolation had inflicted severe economic suffering on Nicaraguans. The US government knew that the Nicaraguans had been exhausted from the war, which had cost 30,865 lives, and that voters usually vote the incumbents out during economic decline. By the late 1980s Nicaragua's internal conditions had changed so radically that the US approach to the 1990 elections differed greatly from 1984. The Bush administration decided to promote an opposition victory and to denounce the country's electoral laws and procedures should there be a Sandinista victory. The United States, through the National Endowment for Democracy, organized a united opposition out of fourteen dissimilar microparties into the National Opposition Union (Unión Nacional Oppositora, UNO). It promoted their candidates including presidential nominee Violeta Chamorro who was received by President Bush at the White House. The US thus "micromanaged the opposition" and exerted massive external pressure on the electorate. The Contra war escalated over the year before the election. The US promised to end the war and the economic embargo should she win.
The UNO scored a decisive victory on 25 February 1990. Chamorro won with 55 percent of the presidential vote as compared to Ortega's 41 percent. Of 92 seats in the National Assembly, UNO gained 51, and the FSLN won 39. On 25 April 1990, Chamorro assumed presidency from Daniel Ortega.