In Ether 13:2-3, Moroni refers to a prophecy by Ether to the effect that,
he told them all things, from the beginning of man; and that after the waters had receded from off the face of this land it became a choice land above all other lands, a chosen land of the Lord; wherefore the Lord would have that all men should serve him who dwell upon the face thereof. And that it was the place of the New Jerusalem, which should come down out of heaven, and the holy sanctuary of the Lord. Behold, Ether saw the days of Christ, and he spake concerning a New Jerusalem upon this land.
In the prophecy of Ether, the phrase “this land” apparently refers to the site where the New Jerusalem would be built. Some have taken this phrase (“this land”) in a narrow (“literal”) sense, meaning that it must have been the specific area where the Nephites and the Jaredites of the record actually lived. However, the context of Ether’s words do not seem to imply a specific area, but refer to the time of the creation, when all the earth was covered with water and then the waters receded from off the land:
And God called the dry land Earth; and the gathering together of the waters called he Seas; and God saw that it was good. (Genesis 1:10)
Thus Ether was probably speaking in general terms of this part of the whole “earth.” This general view seems to better accommodate the prophecies of Joseph Smith. In other words, according to Joseph Smith, while the “city of Zion” (New Jerusalem) is to be built in Jackson County, Missouri (D&C 57:1-5; 84:2-5), the “land of Zion” comprises all of North and South America (see Teachings, p. 362). [Alan C. Miner, Personal Notes]