Of course the Lost Cause was a later construction. That is obvious. The soldiers didn’t run into battle shouting, “For the Lost Cause, Boy’s.”
Moreover, it has long been discredited as an idea and argument.
How do you know for sure that the country believes as you do? If it does, how did we get our current president?
If you would like to invite bullies to your hometown to tell you what you do, then bless your heart. I will make sure they are uncomfortable in mine.