It is available online here: http://publications.maxwellinstitute.byu.edu/fullscreen/?pub=1467&index=4
Sometimes my peer reviews require interlinear text or extensive comments, so I reproduce the entire piece with my notes. This one doesn't require such detailed analysis.
In this piece, Roper reviews the book Prophecies and Promises by Porter and Meldrum. That book makes the claim that the land of promise described in the Book of Mormon refers exclusively to the United States.
In Part I, Promised Lands, Roper claims Porter and Meldrum are "Confusing parts with the whole." Roper asserts that the land of Israel is a land of promise, but there are smaller sections within Israel, or within Canaan, so there can be many lands of promise. He recognizes that the United States is the setting for many important events, and so it can also be a land of promise, as Porter and Meldrum claim. After mentioning the chart of 36 prophecies and promises, Roper writes, "It is erroneous, however, to conclude that such references confine the American land of promise to the United States."
Roper argues that "the 'promised land' of Nephi's vision must include not just the United States or North America, but parts if not all of Central and South America as well." To support his argument, Roper cites 1 Nephi 13:12 and notes that Columbus never visited the United States. This is a common error, but inexcusable in an academic review that purportes to cite facts. The U.S. National Park Service notes this: "This Salt River Bay site is the only known place where members of Columbus's expedition set foot on what is now U.S. territory, and was the site of the first armed clash between Europeans and American natives. On November 14, 1493, on his second voyage to the New World, Christopher Columbus sent a party of men ashore on St. Croix."
So factually, Roper is incorrect (assuming Columbus is the man referred to in 1 Nephi 13:12). And he doesn't mention that Columbus never visited southern Mexico or Guatemala. However, Roper makes a good point that the Book of Mormon refers to "every nation" and "whatsoever nation" that shall possess the promised land, implying there are more nations than one that would exist on the promised land. He cites many examples of Church leaders referring to the entire hemisphere--North and South America--as a land of liberty, based on the U.S. Constitution. He cites George Albert Smith as saying of the Western Hemisphere "that this should be a land of liberty unto the Gentiles."
In my view, Roper makes a strong case that supports George Albert Smith's view. On the other hand, only the United States fulfills many of the descriptions of the promised land, a point Roper avoids. Consequently, it seems that there are multiple definitions of the "promised land," some specific to the United States and others more generally applicable to the entire Western Hemisphere. In a sense, this is akin to the notion of the "House of Israel" as special people. The laws of the gospel apply to all people, regardless of tribe, and covenants associated with land also follow the righteousness of the people. Various people and prophets have been given "promised lands" for themselves and their posterity, conditioned on repentance and obedience to the gospel. In that sense, every place can be a promised land. But it also seems clear that there can only be one "promised land" that was given to Lehi for his family, where the Savior visited the Nephites, where the New Jerusalem will be built, etc. And that one, it seems to me, is in North America.
In Part II, "Looking Beyond the Mark" and Losing the Remnant, Roper briefly mentions DNA studies before focusing on the question of who is a Lamanite. Here Roper engages in rhetorical flourish that undermines his argument. "Porter and Meldrum heap scorn and ridicule upon those who have a more expansive view of hte seed of Lehi, which would include people throughout the American hemisphere and the isles of the sea. They speak with disdain of Latter-day Saints for whom a Mesoamerican setting makes sense, but in doing so they tar the Saints and their prophets with the same brush, for no prophet restricted Lehite ancestry or promises as they do."
Roper cites many LDS Church leaders who have stated that the indigenous people of Latin America are Lamanites. Some have even spoken of the blood of Lehi.
Roper concludes: Unlike Book of Mormon geography, an issue on which the church takes no position, the identity of the American remnant of Jacob is a matter about which Latter-day Saint prophets and apostles appear to have expressed no uncertainty. The diversity of Native American ancestors makes it unreasonable to expect that contemporary DNA studies might prove or disprove the prophetic ancestry of Lehi's people. Attempts to do so are unwise and ill grounded and reflect a misunderstanding of what those studies were intended and not intended to do.
This is an effective argument--in part. Whether the Book of Mormon events took place in North America or Central America, the Lamanites who survived undoubtedly migrated elsewhere. In the thousand years between the demise of the Nephites and the arrival of Columbus, extensive migration and intermarriage occurred. "Mesoamerica as hinterlands" makes a lot of sense and is consistent with the archaeological and anthropological evidence. The DNA evidence shows the indigenous Latin Americans are primarily Asian, but that doesn't preclude some ancestry descended from Lehi.
As a practical matter it is also difficult to distinguish between the promises made to the Gentiles and the promises made to the Lamanites; regardless of what "tribe" one belongs in, every individual has the opportunity to choose light or darkness and everything in between. Everyone has a chance to enjoy the blessings of the gospel, in this life or the next.
Even if, as the DNA evidence suggests, the indigenous Latin Americans are not literal descendants of Lehi, is it incorrect to call them Lamanites? Probably not, given the likelihood that there was at least some intermingling with North American tribes (who are definitely Lamanites, as even Roper concedes). According to the DNA evidence, the Latin Americans are mostly Asian, which is to be expected given the Book of Ether. Although many LDS think the Jaredites were completely annihilated, the text doesn't say that and the archaeological evidence shows extensive migration into Latin America of Asian ancestors. This makes the indigenous Latin Americans Book of Mormon people, even if only tangentially descended from Lehi.
The problem with Roper's argument is it is an ex post facto response to the DNA evidence. Based on the text itself, which describes a remnant of Lehi's people surviving until the last days, it is not "unreasonable" to expect that DNA studies would prove their ancestry. Roper doesn't explain why it is "unwise and ill-grounded" to study DNA evidence.
Despite the practical difficulty of distinguishing between promises to Gentiles and to Lamanites as applied to individuals, the distinction in the Book of Mormon is clear and does retain relevance in today's world. In my view, the specific promises made to the Lamanites in 3 Nephi 16 and 20 are yet to be fulfilled because the time of the Gentiles has not yet been fulfilled. The Latin Americans are Gentiles just as the North Americans are, but that only means the promises in the Book of Mormon made to the Gentiles apply to everyone on the continent. The literal Lamanites will have their day soon enough. Maybe once we more accurately identify who they are--so that they themselves will know who they are--that day will finally come.