BTW you always seem to be forgetting about Payroll and Corp taxes, which bring in more than the income tax does.
1. Fred is 100% wrong. We could easily pay off everything if taxes were increased.
2. No reasonable discussion of flat tax or any changes can be had without addressing the 15 Trillion - you have to pay it and the interest on it off. If interest rates increase, we are doomed by the cost!
3. Payroll taxes are separate because we broke out the medicare and ss...it's easier to keep it simple that way.
4. Many flat tax supporters want to eliminate or lower corporate taxes - so there goes that revenue!
As you surely know, you cannot get blood from a stone. The money must add up. There is no magic bullet here in terms of cuts - as Fred seems to indicate. Even a frugal budget would need 2.5 trillion (net of ss and medicare) to pay off some debt and keep the basics going.
Our existing system is a progressive tax. Most Americans support that. At the same time, it should be simplified and deductions done away with. This effectively makes it flatter. But - no matter how you slice it - the very wealthy are going to have to pay a little bit more if we want to make a dent in the debt. No way around that, even with growth.