Increase the middle class' taxes or retract the promises made to them

James Pethokoukis cites the Urban Institute:

Blame whomever you want for today's current fiscal mess, but don't cling to any myths about how far rescinding recent tax cuts for the rich would go toward meeting the nation's many budgetary shortfalls. Our elected officials simply cannot get around the most fundamental of political dilemmas. Even if they enact additional taxes on the rich—and that would not be easy—they still must either retract many of the promises made to the middle class, increase its taxes, or both.

And they're often labelled liberal