Sam Harris
Letter to a Christian Nation.
Knopf, 112 pages, $16.95

If an author who has written a bestselling book then releases, a scant year later, another book on the same topic, it is fair to pause a moment to ponder why the second book got written. Perhaps he wishes to correct a flaw in the first book; perhaps he wants to expand its scope. Now, Sam Harris’s Letter to a Christian Nation is so much in agreement with and so much more limited in scope than last year’s bestselling The End of Faith that he could only have produced it because he believed the original work wasn’t condescending enough.

His premise, briefly stated, is that religion is bad and ought to be eliminated. (The special focus on Christianity is a nod to the American reader.) The entire book is written in the second person, ostensibly to a Christian; in this way Harris time and again gets to declare what...