This is such an important statement! Most do not comprehend it. Christ and his apostles did preach/teach only the Jews. Christ told Paul that after He was resurrected that Paul was to begin teaching the gospel to the Gentiles.
The fact that Christ, after his resurrection came to the Americas and taught (well, essentially re-established, for they had it before but had fallen) the laminite/nephite peoples is an essential point in understanding that the native American peoples are indeed a remnant of the house of Israel.