San Diego, California (CNN) -- Billionaire Warren Buffett has been thinking about the inequities in the U.S. tax system at least since June 2007. I know this because, during PBS' Democratic presidential debate in which I served on a panel of journalists, I asked the eight Democrats, including Barack Obama, what they thought of comments Buffett had made about the unfairness of a tax system where his secretary paid a higher percentage of her income in taxes than he did. I asked Obama if he agreed with Buffett that the rich weren't paying their fair share, and what he would do about it.
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Ruben Navarrette: Gallup Poll finds majority favor raising taxes on corporations and the rich
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"Buffett Rule" would set minimum tax rate for people earning more than $1 million a year
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Navarrette says this is an election gimmick because Obama knows it won't pass
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Navarrette: In a fair system, everyone would pay the same percentage of income in taxes
The current system, the one @placeholder complains about, is inequitable.