"Nevertheless, thou beholdest that the Gentiles who have gone forth out of captivity, and have been lifted up by the power of God above all other nations, upon the face of the land which is choice above all other lands, which is the land that the Lord God hath covenanted with thy father that his seed should have for the land of their inheritance; wherefore, thou seest that the Lord God will not suffer that the Gentiles will utterly destroy the mixture of thy seed, which are among thy brethren."
This comes after an explanation of how the gentiles will flee oppression in another land (Europe), come here, and overtake this land. Nephi has been shown the establishment of a great church that alters the teachings to be given by Christ to the Jews. Then the prophecy continues with the above statement.
Flight from captivity has brought the Gentiles here. They came here (originally) for religious freedom. They wanted to follow their conscious when it came to matters of God and belief. This land was a land of religious freedom for these gentiles.
They then were "lifted up by the power of God above all other nations." This "lifting up" is not only to enjoy religious freedom to worship God. It also included the power to retain that freedom against any foreign threat to remove it. Therefore, ancillary to the religious freedom, the gentiles were necessarily given economic and military might with which to retain that freedom against "all other nations." But the "power of God" which "lifted [them] up" is conditioned upon them always serving the God of this land, who is Jesus Christ. (Ether 2: 12.) The power of God cannot be used to protect a wicked people.
The land is "choice above all other lands." Why is that so? What is it about the American continent which makes it more "choice" than any other location on earth?
Notice that here again Nephi is told that the land has been given to Lehi's descendants as "the land for their inheritance." Whatever dispossession the gentiles cause, these people have God's covenant to return the land to them. What does it mean to have this land promised by God through covenant to Lehi's descendants? Does that promise contain any condition? Will these people forfeit their right if they are wicked? If they will not forfeit the right, then what will happen to them if they cease to serve the God of this land?
Because of the covenant, the Lord will "not suffer that the Gentiles will utterly destroy" the covenant people? Note the "mixture of thy seed" mentioned to Nephi. Why is Nephi promised a "mixture of thy seed" will be preserved? Does gentile oppression remove the promises to Lehi and Nephi? If not, what then do the promises assure them?
Why does God make a covenant to a worthy prophet-patriarch and bind Himself to fulfill the promise even with a posterity which may not be similarly faithful? Has the Lord done this before with Abraham? With Isaac? With Jacob? With Noah? Even though we knew nothing of these covenants when the gentiles overran the land, are they nonetheless God's promise and something which He will fulfill? How certain should we be that the Lord will deliver this land back to those who descend from Lehi and Nephi?
Why can a righteous prophet-patriarch obtain such promises from the Lord? What reason is there for such covenants to be made? Can they still be made? How? What did Lehi and Nephi do to qualify to receive such a covenant? Was there any intermediary? Will the Lord employ a servant when making such a covenant?
Well, this is interesting stuff. Worth continuing to consider, I think.