Why did the us switch its support from sandinistas to the contras?

The U.S. switched its support from the Sandinistas to the Contras primarily due to concerns over the Sandinistas' ties to the Soviet Union and their Marxist-Leninist ideology, which conflicted with U.S. interests in promoting democracy and countering communism in Central America. The Reagan administration viewed the Contras as a means to undermine the Sandinista government and restore a more U.S.-aligned regime in Nicaragua. This shift was part of a broader Cold War strategy to combat communist influence in the region.