"Or we will lose America as we have always known it."
You say this as if it's a bad thing.
Abolition brought about the end of America as the generation of that age had always done it. The civil rights movement did it again in the 60s.
America has been "lost" many, many times over the last couple centuries. In retrospect, we view most or all of those radical changes as having been for the better. There have *always* been people who benefited from the status quo - at the expense of others - who have tried to portray such change as if it were a bad thing, and history has been appropriately unkind to those individuals - as it will be to you.