ILYA SOMIN: “Libertarian Party presidential candidate Bob Barr is one of many people who confuse the theory of the ‘unitary executive’ with the claim that the executive has virtually unlimited power. Barr argues that ‘McCain has endorsed, in action if not rhetoric, the theory of the “unitary executive,” which leaves the president unconstrained by Congress or the courts.’ In reality, the unitary executive argument is a theory about the distribution of executive power, not its scope.” What’s sad is that so many longtime members of Congress don’t know the difference.