If they can afford a gun they likely have one, but rather than forming sects and training it seems like the moral thing to do, causing the least amount of harm to anybody, is wait for the enemy to attack first, if they do attack.

Joining a small militant group or ecoterrorism sect not only brings personal risks but also runs the risk of harming innocents, and being manipulated by other interested parties who would like to see destruction on American shores.