Economist Stephen Moore, one of the architects of presidential contender Herman Cain’s 9-9-9 tax plan, said Cain needs to rework a critical component of the plan. Cain’s plan would replace the current tax structure with a 9 percent corporate tax rate, a 9 percent personal income tax rate and a 9 percent federal sales tax. But speaking on Larry Kudlow’s radio show on Saturday, Moore said the sales tax should be replaced with a 9 percent payroll tax. “I’ve come to the conclusion that the American people and the voters do not want a national sales tax,” he said. “[Cain’s]...