trying to figure that out also w/ esper.
my hope is that under a worse case scenario, if Potus needs to hand off command for optics or for real, Esper would assume command, even ahead of pelosi, pence and McConnell, for a short time during any active Mil defense.
also where he conflicts w/potus and gets his way it shows potus is not a dictator, and doesnt really weaken potus because the differences in opinion seem minor.
optics and reality show NG is practicing support not defense, and Barr and FBI CT are truly in charge of problems.
Barr and US Marshals swore in a number of MIL or NG likely undercover plain closed but ready. So no Mil per se they are deputized US Marshals.