Since the second amendment only protects a well regulated Militia, the unorganized militia and private militias would not be protected under the second amendment.
State Defense Forces and State Guards are protected -- the California State Military Reserve would fall under that.
(a) The militia of the United States consists of all able-bodied males at least 17 years of age and, except as provided in section 313 of title 32, under 45 years of age who are, or who have made a declaration of intention to become, citizens of the United States and of female citizens of the United States who are members of the National Guard.
b) The classes of the militia are (1) the organized militia, which consists of the National Guard and the Naval Militia; and
(2) the unorganized militia, which consists of the members of the militia who are not members of the National Guard or the Naval Militia.
You need to go back to English Class, the “A well regulated militia being necessary to a free state,” does not say that only if you are a member of a militia do you have an uninfringable individual right to keep and bear arms. It is simply saying that one reason, among many others, that “the right to keep and bear arms shall not be infringed is that a well regulated militia is necessary to a free state.
Ravenstar