Taxes on trade are actually quite harmful to the economy, which is why they are generally avoided except as a way to control the flow of certain goods. You'd damage your exports because of the inevitable retaliatory duties imposed on the export of US goods to other countries. Prices would simply rise, or wages would fall because of higher business prices and you'd be no better off in the end, probably worse off. In terms of economy, income tax is probably the best method of doing things. What's the big deal about abolishing income tax anyway? Do you not want to feel like you're paying for the police/army etc etc? You still would be, just indirectly and less efficiently.