According to Allen Christensen, as outlined in the books of Helaman and 3 Nephi, the problem was not that the Nephites engaged in long-distance trade relationships, but that they used the profits to create a new elite class which placed itself above those with less wealth and sought to deprive them of their liberty (Helaman 3:36; 6:17,39; 3 Nephi 6:11-14)
Communities which participate in international trade tend to build comparatively large, centralized city-states with a bureaucracy of wealthy and powerful merchants and officials. Those who oversee these lucrative trade activities rapidly form a new elite class, and this leads to a gap in wealth between those who participate in the trade of expensive items and those who do not (Sanders and Price 131). [Allen J. Christenson, "Nephite Trade Networks and the Dangers of a Class Society," in The Book of Mormon: Helaman Through 3 Nephi 8, According to Thy Word, pp. 223-231]