I believe that you are saying to start from the top and go down rather than start at the bottom and go up.
IMHO it would be almost impossible to get the entire armed forces of the USA actively involved in an action against a very large portion of the American populace. There would be divisions within the troops and leadership. Thus there would be at least two factions. Further, there would be two factions within most of law enforcement. There would be some who would dearly love being part of units like the Chicago "CAGE" unit and there would be others who would provide information to those resisting.
In short the situation should it ever come down to our needing to see what good an Ameican handgun can do against an army in America is not going to be pretty in an sense of the word. I note that such an army would perforce not be an army primarily of American citizens as they would be notoriously unreliable in killing their own families and neighbors.
Stay well - Stay safe - Stay armed - Yorktown