Sorry to repeat, but I wonder if anyone finds this gambit as distasteful as I do:
Tagej: "we are talking about wealth that has already been taxed"
Not true. Many of the wealthy acquired most of that wealth as a result of appreciated assets, particularly the stock in their own companies. The appreciated wealth is not taxed until the asset is sold. If the asset is still in the estate at death, it is not subject to income tax, and the value basis is stepped up for the heirs, so they can sell it tax-free. Therefore, the only tax it would ever be subject to is the estate tax.
A tax attorney I know is salivating over the potential repeal of the estate and gift tax. He says wealthy younger people would "gift" appreciated assets to their elderly, near-death parents. At their death, the assets would be willed back to the children at a stepped up value. They could be sold and no tax, either income or estate, would ever be paid. Unfortunately, this will only matter to the very rich. Most of us don't have millions or billions tied up in appreciated securities. Note that this also means there is zero reinvestment in business going on under this scenario. Large asset holders just pay less taxes.