Matt, I fully agree with you. Power corrupts and as Selco also experienced some groups that started with well intentions, ended up being pretty bad gangs. It is hard to draw the line but in general I think some sort of small organized militias could provide a lot of stability for an area once the law is gone. (If they stay on white / good side of the spectrum).
Joining a militia “officially” would bother me too. The NSA can easily filter their databases and find certain groups of people. Im under no illusion that if they want to target militias they can find members quickly.
Alea iacta est ("The die has been cast")