Could taxing billionaires’ unsold assets raise enough money to pay for Biden’s ‘Build Back Better’ plan?

Treasury Secretary Janet Yellen described a tax on billionaires that would help pay for President Biden’s ambitious social policy agenda. She told CNN on Sunday: “It would help get at capital gains, which are an extraordinarily large part of the incomes of the wealthiest individuals, and right now escape taxation until they're realized. … It's not a wealth tax, but a tax on unrealized capital gains of exceptionally wealthy individuals.”

The idea gained traction during the 2020 presidential campaign, backed by progressive candidates like Massachusetts Senator Elizabeth Warren. But Biden was lukewarm until recently.