For most of us, our direct experience with American politics starts and ends with the voting booth, supplemented with what we learn, selectively, from the media. We rarely see our elected representatives in action, proposing and bargaining over bills and budgets. In general, politicians rank low on our lists of most admired professions. Nor do we know much about what happens inside those big state and federal agencies.

Recently, the son of a third cousin asked me to advise him on post-college job hunting. We had a spirited meeting at a coffee shop. A recent graduate with a political science...