For those who somehow missed it when growing up, “Atlas Shrugged” is a fantasy in which the world’s productive people — the “job creators,” if you like — withdraw their services from an ungrateful society. The novel’s centerpiece is a 64-page speech by John Galt, the angry elite’s ringleader; even Friedrich Hayek admitted that he never made it through that part. Yet the book is a perennial favorite among adolescent boys. Most boys eventually outgrow it. Some, however, remain devotees for life. And Mr. Ryan is one of those devotees.