(2) the unorganized militia, which consists of the members of the militia who are not members of the National Guard or the Naval Militia.
What militia might this be? Are there currently state militias outside of the National Guard?
Yes, each of the States has the authority to create State militias that are not part of, or paid for by, the United States government. In order to be part of the National Guard they have to be "federally recognized" and meet the training requirements, established by Congress, and set forth in various statutes and regulations. It is possible for someone to lose federal recognition and remain a part of the State militia, but it doesn't happen often.