What would the Buffett Rule actually pay for?

As it turns out, not very much. As Matthew Yglesias points out, numerous policy makers have cited the Buffett Rule — basically legislation that would ensure that billionaires never pay a lower tax rate than their own secretaries — when asked how they’ll pay for some piece of liberal legislation they want to pass. But the Buffett Rule, by itself, would only raise about $5 billion in revenue a year. Not nearly enough to make much headway on education, infrastructure, and healthcare initiatives liberals want to pass:

Meanwhile, the popular liberal proposal for a “Buffett Rule” on high-end investment income would raise about $5 billion a year. That’s a bit less than half the $12 billion annual cost to the federal government of a Center for American Progress plan for a universal pre-K program. Except CAP’s program envisages joint state-federal fiscal responsibility, so states would need another $12 billion. And yet it’s been turned to again and again as a way of paying for things. It was going to finance a job creating stimulus program at one point, then Chuck Schumer wanted it to offset an R&D tax credit, and now Elizabeth Warren is using it to pay for student loan refinancing.