BYRON YORK: Herman Cain's 9-9-9 plan sounds good; will it work? One objection: "9-9-9 would add a national sales tax on top of current income and business taxes, and would thus give Congress another tax to raise. Why couldn't 9-9-9 become 12-12-12? Or 15-15-15?"

But isn't that true of all taxes? All things considered, I would judge that the benefits of a relatively simple and (hopefully) stable tax system outweighs the potential risk.