Scorpion-tailed wasp thing?
My fiancee and I came across this interesting looking bug in Frozen Head State Park, which is in the town of Wartburg, Tennessee (eastern TN.) It didn’t move for quite a long time, though it was alive.
This amazing creature is an American Pelecinid. It is related to wasps, but does not sting. Your specimen is a female. She uses her long abdomen as an ovipositor to place eggs underground on beetle grubs. The larvae parasitize the grubs of June Beetles.