There was a movie called The Siege, came out in 1999 or 2000, where in the military is used to secure, patrol and police New York in the wake of a terrorist attack. The General in charge of the operation refused to do it early in the movie, saying thusly:
“The Army is a broadsword, not a scalpel”.
Yes it’s a bit of movie dialogue but it’s not untrue. Outside of the special forces the military, US especially, is run on the maxim of go big or go home. They are not the appropriate entity to police elections. It is laughably outside their fields of expertise and training.