No, you got yourself, again.
All I have on my side is the Constitution...
No you don't:
The Constitution, to a large degree, is whatever at least five Justices (a majority) interpret it to be at any given time, based on their ideology, and regardless of what the Founders intended or the expectations of the citizenry (that includes you).
Here's where I have a problem with this line of thought. I took an oath to defend the Constitution when I enlisted in the Army. Let's say hypothetically that one day years from now, the Supreme Court rules that the gun-grabbing groups which define the "militia" as each state's respective national guard is the correct definition, and that firearm ownership by citizens is hereby illegal. At this point, am I justified in using deadly force to defend that right as I interperet it, rather than how the SCOTUS defines it, using Constitutional rights as my justification?
Keep in mind, the Founding Fathers made the wording of the Constitution simplistic for a very good reason.