Well, obviously it wouldn’t change my views that much. But the more interesting question is what would the Church do?
The obvious initial reaction would be “oh, if they’re made in the 19th century, then these aren’t Joseph’s plates”, and life goes on. There are simply too many problems with “finding the plates”; they could have been manufactured by old tyme anti-mormons and forgotten. They could have been a prop in an early Palmyra roadshow (I believe the revelation restoring roadshows to the Lords Church was given shortly after publication of the Book of Mormon). It just wouldn’t stick.
The only way it would be a “problem” would be if the Church has had them all along, and finally produced them for testing. Then there could be no doubt as to their authenticity. But I would expect the Church to conduct such tests privately. If it were to do so publicly, and the result was negative, then this is how I would expect it to play out:
– 14% of active members would refuse to believe it. They would think God had changed the nature of the plates as a test of their faith.
– 9% of active members would be kind of confused, but continue to believe the Book of Mormon is a literal history revealed to Joseph as revelation using the plates as a conduit or prop.
– 77% would never hear about it, and would consider it an anti-Mormon lie if they did.
– 100% of inactive members would shrug their shoulders and return to their depraved, hedonistic, coffee drinking lifestyle.
Over the next 36 years, the Church would slowly shift it’s focus from a literal belief in the Book of Mormon. Eventually, there would be fewer mentions of it in conference and church magazines. The curriculum in Gospel Doctrine would be changed so we don’t study different scriptures each year. Missionaries would focus on the First Vision and modern revelation, with hardly a mention of the Book of Mormon. The Church would begin publishing a “condensed” version of the Book of Mormon in pamphlet form, and over time, this would become the accepted version, and folded into the Pearl of Great Price. Church movies would still show Christ visiting the new world, but they wouldn’t look like Mayans, but instead they would be bearded Caucasians again.