According to Richard Rust, with respect to modern-day Lamanites, the overall structure of the Book of Mormon is like a triangle. The book begins and ends with concern for the Lamanites' receiving the gospel. . . . At the apex of the triangle is an account of a great spiritual change among the Lamanites. That is the turning point because it is the climax of centuries of efforts to bring the gospel to the Lamanites and because of the opposing forces it brings on.
This apex occurs in the physical center of the Book of Mormon. The section of Alma that includes chapters 23 through 26 (which is just one chapter, Alma 14, in the first edition) treats a wholesale conversion of the Lamanites. This central part begins with the decree of the king of the Lamanites that Ammon and his brethren should be free to preach the word of God throughout all the land and ends with gratitude expressed by these great missionaries for the thousands of Lamanite souls "brought to behold the marvelous light of God" (Alma 26:3). The earlier warlike and reprobate nature of the Lamanites has given way to the wholehearted acceptance of the gospel once converted. [Richard D. Rust, Feasting on the Word, pp. 234-235]