cuz I ain't Isaac Asimov. I do better on analysing a given data set, present or historical.

from you

JMM: What are the reasons for the central government to be so interested in this area - so that it has to deal with insurgents, criminals and concerns about firearms and munitions ?

JMM: What reasons (if any) are there for the central government and the local population to cooperate on issues - if so what are the co-operative areas (what are the win-wins) ?
If we're talking about my neighborhood, I could tell you
Obviously what I'm looking for are any useable "bridges" from the central government to your "Obstinentinians", but also what "dams" separate the central government from them.

As I see the scenario, your large, neutral unless gored, armed group is the political key to the area. The armed insurgents are not in the mobile warfare phase, but can bite. I'm also including some renegade criminal gangs (you might not have them; but they were in the SF author's OP scenario and could be expected in an area of unrest) that can bite. I'm positing that the insurgents and criminals are part of your population group; and that whatever problems they present will be finally resolved only if your population group is involved.

An historical example (which provides no cookbook answers; and your population might not like some of the recipes actually used), on a macro level, of a new national government (saddled with excess baggage from the past) having to deal with armed insurgents, armed criminals and armed semi-autonomists, was SVN ca. 1955. Briefly, over 100K of the Viet Minh military and political cadres had gone North (temporarily) as regroupees, leaving perhaps 10-15K cadres in the South. Diem's initial problems were the Saigon Mafia and two well-armed religiious sects near Saigon (Wiki):

Diệm's position at the time was weak; Bảo Đại disliked Diệm and appointed him mainly to political imperatives. The French saw him as hostile and hoped that his rule would collapse. At the time, the French Expeditionary Corps was the most powerful military force in the south; Diệm's Vietnamese National Army was essentially organised and trained by the French. Its officers were installed by the French and the chief of staff General Nguyen Van Hinh was a French citizen; Hinh loathed Diệm and frequently disobeyed him.

Diệm also had to contend with two religious sects, the Cao Dai and Hoa Hao, who wielded private armies in the Mekong Delta, with the Cao Dai estimated to have 25,000 men.

The Vietminh was also estimated to have control over a third of the country.

The situation was worse in the capital, where the Binh Xuyen organised crime syndicate boasted an army of 40,000 and controlled a vice empire of brothels, casinos, extortion rackets, and opium factories unparalleled in Asia. Bảo Đại had given the Binh Xuyen control of the national police for 1.25 m USD, creating a situation that the Americans likened to Chicago under Al Capone in the 1920s.

In effect, Diệm's control did not extend beyond his palace.
So, nothing new under the sun - the problem of firearms and munitions "control" (over groups not overtly "enemies") has been, is and will be with us in "small wars" in many guises.

Two other adds to the scenario.

1. The local population has members in the police (how about the higher grades, "Os" and "NCOs"), but apparently not in the military. Reasons for that ?

2. What is the relationship between the local population elites and the national power elites ? E.g. (not saying it's this), semi-feudal, neo-colonialist, comprador bourgeoisie (as one type), or something different.

Feel free to ruminate.

Mike