If you haven't heard of the Buffett Rule, you will. It's already emerging as one of the key themes of the presidential race, and if it isn't already known as the Romney Rule, it will be soon.
Conventional wisdom has always held that running class warfare against the rich doesn't work because middle-class Americans actually like (and aspire to be) rich people, and that the worst thing a presidential candidate could do is promise to raise taxes. In 1984, Vice President Mondale said that whoever the next president was would raise taxes. "He won't tell you. I just did." Great line. Great theater. Disastrous politics.
But that was then. Ronald Reagan never seemed like a rich guy, even though his friends were. The economy was in full-blown recovery. People still believed you could cut taxes, increase defense spending and balance the budget -- even though the deficit was already ballooning.
This is now. The rich have gotten richer, and they pay a lower percentage of their income in taxes than middle-class voters. I'm not exactly sure how they do it, but billionaire Warren Buffett pays a lower percentage than his secretary. And Mitt Romney pays a lower percentage than my secretary.