Disparity existence in USA

The United States has one of the highest income disparities in the world. The gap between the rich and the poor continues to grow. Other nations, such as Scandinavian (Nordic) countries, have much lower income disparities. Discuss some possible reasons why such dissimilarity exists among highly developed nations ( specifically the United States and Scandinavian countries). What should be done, if anything, to combat such an income disparity in the United States? Provide at least three specific examples how would you resolve this inequality problem.