Now that George W. Bush has finally left office, here's a challenge to a nation famous for its proud tradition of invention: Can somebody invent a machine capable of fully measuring the disaster that was the Bush presidency?

Yes, yes, I know that attitudes towards presidencies are volatile. Harry Truman was hated when he left office and look at him now; he's so highly regarded that President Bush thought of him as a role model. There are, I'm sure, still a few William Henry Harrison dead-enders around, convinced that the 31...