The greatest trick any politician can pull off is to get his self-interest and his principles in perfect alignment. As Thomas More observed in Robert Bolt’s A Man for All Seasons, “if we lived in a State where virtue was profitable, common sense would make us good, and greed would make us saintly." Which brings me to Senator Rand Paul, the GOP’s would-be Man for All Seasons. Paul emerged from the smoldering debris of the Republican health-care-reform train wreck as a figure of high libertaria...