Source: Reuven S. Avi-Yonah, Challenge, Vol. 57 no. 3, May-June 2014
From the abstract:
The author shows that a progressive income tax has had little effect on after-tax income inequality. Social programs, however, do create a more equal society. He proposes a national sales tax—a value-added tax—to finance more such social programs as America’s best route to a more equal society.