For one example (of which there are hundreds), research the US involvement in Guatemala during the civil war. They sponsored and carried out the killing of six Jesuit priests during that time (not to mention Oscar Romero). They meddled and completely abandoned the country when the people were finally allowed to vote. They created conflict for the country and left them to deal with the damage. If you want the true extent of it, look into our involvement in Honduras, Bolivia, and to take the cake - EL SALVADOR!
They, (The USA) have meddled in every country in South and central America since the inception of those countries, many of which the USA had disputes about their border concerns, Columbia and Panama comes to mind right off. We, (The USA) have killed the opposition parties, slaughtered thousands of peasants, burned villages, created coups, financed despots, stolen valuable resources and left behind mountains of slag and lakes of chemicals, killing thousands with cancer, a disease never encountered before US intervention, and for exposing these truths, I've been labeled Anti-American by the righties. Go Figure. I'm very pro-American, Just not pro-American government.