As changing technologies and preferences make government-funded broadcasting increasingly preposterous, such broadcasting actually becomes useful by illustrating two dismal facts. One is the immortality of entitlements that especially benefit those among society’s articulate upper reaches who feel entitled. The other fact is how impervious government programs are to evidence incompatible with their premises.

Fifty years and about 500 channels ago, the Corporation for Public Broadcasting was created to nudge Lyndon Johnson’s Great Society -- it aimed to make America great for the first t...