“Your representative owes you, not his industry only, but his judgment; and he betrays, instead of serving you, if he sacrifices it to your opinion.” So said British statesman Edmund Burke in his famous 1774 speech to the electors of Bristol. Similarly, James Madison wrote in Federalist 57 that voters should choose the candidates “who possess most wisdom to discern, and most virtue to pursue, the common good of the society.” Wise counsel, albeit forlorn in today’s campaign world in which most people—especially primary voters—back the candidates who are most shameless in sacrificing their judgment to the voters’ opinions. Burke...