Oh, I would heartily approve of a national sales tax on the provision that all income based government deductions were removed and never allowed while the national sales tax is in effect.
Even the libs should support it. After all, it has that oh-so-important aspect of taxing the rich more than the poor (as the rich buys more stuff or more expensive stuff) and it definitely has a large endorsement for having people save money (i.e. if you don't spend, you're not taxed) built into it's very nature.
You should like the FairTax then since it eliminates the income tax, the corresponding tax code, estate tax, gift tax as well as the IRS - and it requires the income tax records to be destroyed. It also calls for the repeal of the 16th amendment.