Why did the united states sponsor the contras in nicaragua?

The United States sponsored the Contras because they were against the Sandinista government which was in place at the time in Nicaragua. The Sandinista government was a national reconstruction government, but it was a government that the United States viewed as communist. It came at the time where the United States was extremely weary of the Soviet Union and communist rule and a time when Reagan was president and his foreign policy was based very much on stopping opposing ideologies from gaining ground anywhere in the world.

Iraq because its lack of policing and government concern

Democracy and darwinism would be my answer.