Here . He argues that down the road, taxes are going to have to rise over time to fund Medicare, and not just on the top 1%. He presumes that Americans will continue to support Medicare and demand that it stay in place. He's probably right. He mentions in passing that the top 1% pay 25% of the Federal taxes. Not income taxes, because that number is almost 40%  in the latest available data. I assume he is accounting for payroll taxes.