Is the book of Mormon the foundation of Mormonism?
If so, then how do you account for clear DNA, archaeological, and linguistic evidence that all point the ancestry of Native Americans to North Eastern Asians/Siberians? As far as genealogy, language similarity, cultural similarity, and everything else is concerned, Native Americans are descendants of Asians. Did Israelites somehow forget their heritage, bleach their DNA, and completely altered their appearance between the time they landed in America to the time Europeans came in contact with the Americas?
Since all the stories in this book of Mormonism is based on the existence of Lamanites and other "descendants" of Israelites, does the fact that these descendant never existed disprove those accounts? And if those stories never existed, did the prophet Smith not lie and deceive his followers by claiming he discovered gold plates written by non-existent fictional characters?
Many Mormons tries to find excuses around concrete scientific data and consensus by claiming God is merely tasking the faith of his followers by changing the DNA make up of native Americans, but I hope that excuse is too silly for even the least open-minded Mormons. It's Christian church claiming the Sun still orbits the Earth but God is merely making it seem like we orbit the sun to test our faith. If you use that excuse, you can explain ANYTHING away.