To address a few points: The Early Americas were, at the time of Joseph Smith, thought to have been verdant, unpopulated areas with no understanding among historians and anthropologists as to the number and variety of populations that had arrived in South America. Joseph was criticized for saying that "many people" had come to the continent. It was beyond the understanding of the science of the time. Now that has changed. We now know that many "peoples" have inhabited the land. Many have come and gone and many have mixed with the people of this "new country." Joseph was criticized for including them in the beginning, and now he is criticized that they existed at all given modern day understanding of science. He said there were many people long before science believed this to be the case. Now it is understood. Argue what you want... he saw it long before the science of the day and it has come to pass.