[Jan Shipps is a professor emeritus of history and religious studies at Indiana University-Purdue University Indianapolis, and the author of "Mormonism: The Story of a New Religious Tradition."]

When Mitt Romney gave his "Faith in America" address last Thursday, observers wondered how "Mormon" it would be. "Not very," is the understandable consensus. Mormonism 101 it was not, and he said very little about his personal religious beliefs, sticking to his announced topic.

Still, in the way he talked about religious diversity, the nation's symphony of faiths, the way religious liberty stands at the heart of the American constitutional system, and how religion belongs in the public square, this was a consummate Mormon speech. Moreover, despite its political agenda, it is possible to read what Mr. Romney said as being in harmony with a major effort his church has been making since the 1970s: to be included in the American religious mainstream.

An intriguing element running through Mormon history is its tension with American culture. The faith's founding prophet, Joseph Smith Jr., emphasized the unique character of Mormon teachings. He produced a new sacred text, the Book of Mormon, and his revelations inaugurated a new dispensation in which the ancient priesthoods and the authentic New Testament Church of Christ were restored to earth. Such claims implied that all other churches were in error.

The first reaction was ridicule and charges that Mormonism is heresy, with hostility and frightful persecution following thereafter. Smith's revelations led to the added claims that Mormonism was the restoration of Israel in the new world and that the restoration of the ancient order of things had commenced. Among much else, this meant the inauguration of plural marriage (polygamy).

After 50 years, the resulting conflict between Mormonism and the nation's churches and federal government reached such an impasse that the Mormons were compelled to suspend polygamous practice.

What happened next is a genuine paradox. Instead of reacting negatively to this government pressure, the Mormons began to venerate the nation. A half century later, they were archetypal Americans. The Mormon Tabernacle Choir became "America's choir," and during the 1960s, the contrast between straight-arrow, neatly dressed, and well-behaved Saints (Mormons) and hippie culture heightened the perception that Mormons are as American as motherhood and apple pie.

In the 1980s, however, superconservative Evangelicals turned their attention to Mormon theology. Along with some articulate ex-Mormons, they tried to convince the world that Mormonism is a cult whose members are not Christian.

In response, the Church of Jesus Christ of Latter-Day Saints (LDS) added "Another Testament of Jesus Christ" as a subtitle to the Book of Mormon. And the church changed its logo to place more emphasis on the Jesus Christ part of its name. Additionally, Christendom's founding stories became standard fare in virtually all materials published by the church....