Seidman, Laurence S., “Pouring Liberal Wine into Conservative Bottles. Strategy and Policies,” University Press of America, Lanham, Maryland, 2006

“With the retirement and greater longevigty of the baby boomers looming on the horizon, and the corresponding projected rise in the percentage of GDP that will be absorbed, even with fiscal discipline, by Medicare, Medicaid, and Social Security, it will be difficult to reduce large projected budget deficits without substantial additional tax revenue.”
“…(R)ather than rely solely on the current arsenal of taxes to raise the revenue, it would be better to put some of the burden on a new PVAT (Progressive Value-Added Tax),” p.113