Highly educated people say the darndest things, these days particularly about the tea party movement. Vast numbers of other highly educated people read and hear these dubious pronouncements, smile knowingly, and nod their heads in agreement. University educations and advanced degrees notwithstanding, they lack a basic understanding of the contours of American constitutional government.

New York Times columnist Paul Krugman got the ball rolling in April 2009, just ahead of the first major tea party rallies on...