Safe from whom or what?
I'd begin with a "Neighborhood Watch" type of program with related or secondary grassroots efforts. Training, communications, training, medical, training, media (winning their hearts and minds?), training, logistics, and training, etc are all needed when dealing with Militia type matters. Think enlarged, adult Boy Scout Troop (definitely formed on military type grouping).
In fact, while I wouldn't say BSA is THE answer, Lord Baden Powell (and ET Seton) had certain things in mind when he formed that organization and it might do to borrow heavily in a similar slant.
Association with local Sheriff Search and Rescue might be another useful direction.
Questions I would need to answer might be:
What is the purpose?
What is the Plan to accomplish said purpose?
On what/whose Authority will it fall under or serve?
Who will fund/pay any bills?
How will it be organized?
(and please Lord, don't let it be old, fat, out of shape guys, dressed in camo, running around in woods shooting guns, then retiring for the night to go off to drink beer, feeling good about scaring squirrels and making noise alone) Seriously, if your plan is to help your community and be of service, I'm all for it. I'd just be leery of my parenthetical snark or of any political factions that might develop within. Remain service oriented, apolitical (if possible) and non-threatening.