Most people are familiar with the argument that a Value-Added Tax
(VAT) like Europe has, is an invitation to tax hikes. Japan is
providing new evidence of this. The country introduced a consumption
tax of 3 percent in 1988, raised it to 5 percent in 1997, ensuring the
90s would be a “lost decade,” and now has considerations to increase it
to at least 8 percent and possibly more than 10 percent  with its
revenue dedicated to social welfare costs — including pensions and
medical and nursing programs.

For all you Boortzers, this sounds like a serious downside that more than covers the benefits of ending the IRS.