Will USA economy tank if ww3?

Will USA’s economy ever turn out like Japan’s economy where stocks never recovered?
Also, how likely is it if USA loses its spot with the reserve currency?
If ww3 happens, and IF USA isn’t a world power will the usa stocks tank?
Just some food for thought.
Ray Dalio is saying that currently there is a fight for world power… and that had me thinking…
What are your thoughts?