Null-ABC by H. Beam Piper, Science Fiction, Classics, Adventure

Literate First Class Elliot C. Mongery, revealed by a quick left quarter-turn of the pickup camera, wore the same starchy white smock, the same Sam Browne belt glittering with the badges of the organizations and corporations for whom he was authorized to practice Literacy. The tablet on his belt, Pelton knew, was really a camouflaged holster for a small automatic, and the gold stylus was a gas-projector. The black-leather-jacketed bodyguards, of course, were discreetly out of range of the camera. Members of the Associated Fraternities of Literates weren't exactly loved by the non-reading public they claimed to serve. . . .

Imagine a world where that bookish nerd over there really does have the power of life and death over everyone around him. . .