It is not just Republican presidential candidates who cannot be bothered to articulate a coherent argument, instead of ad hoc talking points. Have you yet heard House Speaker John Boehner take the time to spell out why Barack Obama’s argument for taxing “millionaires and billionaires” is wrong?

It is not a complicated argument. Moreover, it is an argument that has been articulated many times in plain English by conservative talk-show hosts and by others in print. It has nothing to do with being worried about the fate of millionaires or billionaires, who can undoubtedly take care of themselves.

What we all should be worried about are high tax rates driving American investments overseas, when there are millions of Americans who could use the jobs that those investments would create at home.

Yet Obama has been allowed to get away with the emotional argument that the rich can easily afford to pay more, as if that is the issue. But it will be the issue if no one says otherwise.