Herman Cain has been gaining much traction with his 9-9-9 Plan, a bold proposal to replace our dysfunctional tax code with what could be a simpler, less invasive, and more economically stimulative alternative. While I don't agree with the full spectrum of Mr. Cain's policy choices, I applaud his courage on the tax front. Judging by his rising poll numbers, this appreciation is widely shared. However, the plan has deep flaws, the most glaring of which is its creation of a hidden payroll tax which represents a fourth "nine." This serious pitfall has been unmentioned by Mr. Cain and overlooked by those who have analyzed his plan.

Cain would replace the current system of income and payroll taxes with a 9% flat-rate personal income tax, a 9% corporate tax, and a 9% national sales tax. Great idea. Such a system would unburden businesses, provide a tax cut for most Americans, and shift taxation to consumption and away from income generation. This is exactly what our economy needs. But unlike our current corporate tax system, the plan eliminates the deductibility of wages and salaries from corporate income. The net effect is the creation of a brand new 9% tax on wages. When this fourth 9 falls from Cain's sleeve, many of his opponents will likely accuse him of cheating.

Much of the plan's virtue lies in its elimination of Social Security and Medicare taxes (payroll taxes) that fall heaviest on lower income workers. This includes the 6.2% Social Security tax and the 1.5% Medicare tax paid directly by the worker. But it also includes the 6.2% and 1.5% portions paid indirectly by workers through their employers. Payroll taxes are, in reality, a cost of employment. From the employer's perspective these costs are part of the wage package. Absent these taxes, employers could raise wages by an equivalent amount without raising labor costs. Inclusive of this portion, payroll taxes currently cost workers 15.4% of their wages.

The Cain plan scraps this tax. But the elimination of wage deductibility from corporate taxes replaces it with a 9% payroll tax. Therefore a more honest name for Cain's proposal is the 9-9-9-9 plan. The forth nine changes everything.

Cain admits that the 9% sales tax would fall heaviest on the poor, but he claims that the elimination of the payroll tax would more than compensate. But when the hidden 9% payroll tax is factored in, more than 50% of workers who currently pay an average income tax rate of just 3% would see a huge tax hike, from 18.4% (former payroll tax plus income tax) to 27%: 9% payroll tax, 9% income tax and 9% consumption tax (poorer worker generally spend all income).

On the other hand, high income tax payers get a huge break. Not counting the consumption tax, the 9-9-9 plan reduces the highest marginal tax rate from 38% (35% income tax and 3% payroll tax - on income over $105,000) to just 18% (9% income tax plus 9% payroll). For the self-employed, who can transform their wages into dividends (that are deductible business expenses under the 9-9-9 plan), the rate would fall to just 9% (all income tax, no payroll or business tax). Of course, in either case, the 9% sales tax will apply to spending, but even if 100% of earnings are spent (which is generally not true of high earners) the top rate would still top out at only 27% for the highest salaried employees and just 18% for the self-employed. In essence, tax cuts for the rich are paid for with tax hikes on the poor and middle class. If these aspects were widely known the plan would become a political dead letter.

Even with its flaws, the 9-9-9-9 plan would create an economic windfall by lowering the top corporate rate to 9% from 50% (35% at the corporate level and 15% on dividends taxed at the individual level), and simplifying the tax code to reduce unnecessary compliance costs and the economically inefficient behavior that is created by perverse tax incentives. These changes alone will make America far more globally competitive. Also by taxing individuals based more on what they spend rather than on what they earn, the plan will encourage more savings (which is a key ingredient for economic growth). As a result, the economy will grow faster, generate greater output of goods and services, and create more jobs.

The problem for Herman Cain is that unless he slashes government expenditures, his pro-growth tax structure will inevitably shift more of the tax burden to low and moderate-income people. The only way to combine tax reform with tax reductions for most taxpayers is to shrink government to a more manageable scale.

The size of the tax increases required to keep Cain's 9-9-9-9 plan revenue neutral demonstrates just how high a percentage of our current taxes are being paid by affluent taxpayers. Couples making more than $250,000 and individuals making more than $125,000 only constitute about 3% of taxpayers but pay almost half of all taxes. Any policy that cuts their taxes will inflict a disproportional hit on government revenue.

Contrary to the rhetoric emanating from the American left, the "rich" are currently paying a lot more than "their fair share." It is only a handful of mega-rich, those whose entire incomes are derived from dividends and capital gains, rather than salaries or business profits, who have the ability to pay lower tax rates than some members of the middle class. The left knows this but continues to build their "free loading millionaire" straw man because it makes good politics.

In the final analysis, if Cain really wants a 9-9-9 plan that doesn't raise taxes he needs to remove the hidden 9% payroll tax. However, the only way this could be done, without blowing an even bigger hole in the federal deficit, is to combine his plan with significant spending cuts. If he can pull that off, three nines may be a winning hand after all.

Peter Schiff is president of Euro Pacific Capital and author of "How an Economy Grows and Why it Crashes."

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