Right here in River City

There is a popular false tradition among us Gentiles that goes like this: 

"Soon we will be responsible for building the New Jerusalem, right here in our very own America".

The truth as received in the scriptures, explains the following: Once the people of this land are humble, ready and find themselves worshiping Jesus Christ (the God of this land), then, and only then, will Zion come down from heaven and be established among the New Jerusalem in America and Jesus will dwell there.  

By the time Zion actually arrives in America, the world, including America, will feel dramatically different.  Our relatively prosperous and peaceful circumstances will no longer exist.  At that time, the king of Assyria (from Isaiah) will be sweeping the nations of the Earth before him.  The world will be completely at war, and the only place survivors may flee for protection will be Zion.

Who are the people responsible for this land of America and for building the New Jerusalem on this land?  

According to the Book of Mormon, the people who received this honor and mandate directly from Jesus Christ, are a remnant from the tribe of Joseph/Jacob.

https://scriptures.info/scriptures/bofm/3nephi/10

"But if they (the Gentiles) will repent, and hearken unto my words, and harden not their hearts, they shall come in unto the covenant and be numbered among this the remnant of Jacob, unto whom I have given this land for their inheritance

(Who was given the land?  The remnant of Jacob/Joseph, the people of the land).

And they (the Gentiles) shall assist my people, the remnant of Jacob, and also as many of the house of Israel as shall come, that they (the remnant of Jacob) may build a city which shall be called the New Jerusalem. And then shall they (the Gentiles) assist my people, that they may be gathered in, who are scattered upon all the face of the land, in unto the New Jerusalem. And then shall the Powers of Heaven come down among them, and I also will be in the midst".

Notice, the responsibility for establishing the New Jerusalem was not given to the Gentiles, as our instruction involves assisting.  The most noted Gentile assist mentioned in the scriptures is the sharing the scriptures (Book of Mormon and Bible) with the remnant of Joseph/Jacob.  

Who are the people in the Book of Mormon that fit this description of the remnant of the house of Joseph/Jacob? 

Correct, the Native Americans of North and South America are the people being described throughout the Book of Mormon as the remnant of Joseph/Jacob.  

How many Native Americans are currently living in North and South America?

Fifty three million!

Recent estimates for North America are close to eleven million, with approximately two million Native Americans located in Canada and seven million living within the U.S.  South America is estimated to contain forty two million indigenous peoples living there.

In the record of Ether, in the Book of Mormon, Moroni explains which people will be building a holy city unto the Lord, and the Gentiles are not even mentioned:    

"Ether taught 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 dwelt 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. And he spake also concerning the house of Israel, and the Jerusalem from whence Lehi should come — after it should be destroyed, it should be built up again, an holy city unto the Lord (wherefore, it could not be a New Jerusalem, for it had been in a time of old, but it should be built up again and become a holy city of the Lord, and it should be built up unto the house of Israel) and that a New Jerusalem should be built up upon this land unto the remnant of the seed of Joseph, for which things there has been a type. For as Joseph brought his father down into the land of Egypt, even so he died there. Wherefore, the Lord brought a remnant of the seed of Joseph out of the land of Jerusalem, that he might be merciful unto the seed of Joseph, that they should perish not, even as he was merciful unto the father of Joseph, that he should perish not.

Wherefore, the remnant of the house of Joseph shall be built up upon this land, and it shall be a land of their inheritance. And they shall build up a holy city unto the Lord like unto the Jerusalem of old. And they shall no more be confounded until the end come, when the earth shall pass away. And there shall be a new heaven and a new earth. And they shall be like unto the old, save the old have passed away and all things have become new. And then cometh the New Jerusalem; and blessed are they who dwell therein, for it is they whose garments are white through the blood of the Lamb; and they are they who are numbered among the remnant of the seed of Joseph, who were of the house of Israel. And then also cometh the Jerusalem of old and the inhabitants thereof; blessed are they, for they have been washed in the blood of the Lamb. And they are they who were scattered, and gathered in from the four quarters of the earth and from the north countries, and are partakers of the fulfilling of the covenant which God made with their father, Abraham. And when these things come, bringeth to pass the scripture which saith, There are they who were first who shall be last, and there are they who were last who shall be first".

https://scriptures.info/scriptures/bofm/ether/6

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