This appears to be a specific reference to the scattering of the Lamanites, the Lord’s covenant people, at the hands of the American settlers. Nephi wrote:
“After all the house of Israel have been scattered and confounded, … the Lord God will raise up a mighty nation among the Gentiles, yea, even upon the face of this land; and by them shall our seed be scattered. And after our seed is scattered the Lord God will proceed to do a marvelous work among the Gentiles, which shall be of great worth unto our seed ... unto the making known of the covenants of the Father of heaven unto Abraham, saying: in thy seed shall all the kindreds of the earth be blessed.” (1 Nephi 22:7-9.)