Under Socialist Party of America presidential candidate Eugene V. Debs, socialist opposition to World War I led to the governmental repression collectively known as the First Red Scare. The Socialist Party declined in the 1920s, but the party nonetheless often ran Norman Thomas for President. In the 1930s, the Communist Party USA took importance in labor and racial struggles while it suffered a split which converged in the Trotskyist Socialist Workers Party. In the 1950s, socialism was affected by McCarthyism and in the 1960s it was revived by the general radicalization brought by the New Left and other social struggles and revolts. In the 1960s, Michael Harrington and other socialists were called to assist the Kennedy administration and then the Johnson administration's War on Poverty and Great Society while socialists also played important roles in the civil rights movement.