Depends on how fast he's moving.
Not to him.
The idea that a self-organized citizen militia could take on and defeat the US Army, Navy, and Air Force is simply laughable.
Well, at least we wouldn't be alone -- all US Marines are sworn to support and defend the United States Constitution against all enemies, foreign and domestic. Indeed, if the Marine Corps is doing it's job, it's likely that it has a contingency plan for the unlikely possibility of the Army, Navy, and Air Force somehow becoming enemies of the Constitution.
What is laughable is that a military person would consider the Second Amendment a paper tiger. What oath did you take?
No militia is capable of withstanding the kind of destructive force a modern combat team (a company of mechanized infantry, a troop of tanks, and two artillery pieces) is capable of putting out.
A militia composed of the entire able-bodied male population of the United States just might, through sheer number of reinforcements. The military experience of many of the militiamen may also be more useful than you allow in your assertion.
Other considerations include terrain, resupply from stockpiles after production by The People has halted, and
Don't listen to this one, Americans. It ain't over 'til it's over.
"Sometimes insanity is the only alternative" -- button at a Science Fiction convention.