The not-at-all-right-wing Lane Kenworthy writes:
Moderate or high levels of tax revenue can’t come solely from higher
rates or new taxes on the rich; the math simply doesn’t work. To
significantly increase spending on transfers and/or services, President
Obama and/or his successors will need to increase taxes on the middle
class. One way to do this would be via a federal consumption tax, such
as a value-added tax (VAT).
I would like to see a betting market in when this is first mentioned by the Obama administration. I don't think it will be very soon, but it will be within eight years' time.