(Investor’s Business Daily) President Obama brought the Buffett Rule front and center in his re-election campaign this week, but legislation to implement it has a major exemption that would reduce likely tax revenue and discourage productive investment.

If passed by Congress — highly unlikely — the Buffett Rule would require everyone with an income of $1 million or more to pay a 30% minimum federal income tax. It’s named after billionaire Warren Buffett, who famously said his secretary paid taxes at a higher rate than he did.

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