Sinead O'Connor is, by its definition, a one-hit wonder in the United States. Her worldwide hit was the Prince-penned "Nothing Compares 2 U" in 1990, which topped music charts across the world and was nominated for a Grammy award. Unfortunately, her 2nd biggest mark in the US was this infamous Saturday Night Live appearance where she covered Bob Marley's "War" a cappella and then tore up a picture of Pope John Paul II in a protest against the Catholic Church.
While O'Connor never achieved consistent musical success in the American mainstream market, she was still a major hit in her native Ireland.