I don’t expect Trump to win in the courts, but let’s say he does you don’t think we’ll be facing unprecedented looting and riots ? The kind of which will only go away with an army of force ? I don’t think he’ll win but we are in year 2020. I won’t be shocked.
I don't think the initial action that sets everything off is realistic, but if it somehow came to be, I don't doubt we'll need the military in the streets. However, that would be the National Guard, and the President doesn't need SECDEF to have them deployed. Is Trump preemptively getting rid of any obstacles? Maybe.
It's an interesting theory, but I'd lean more towards international issues at play.