I know ALL about the NRA Wolf - we just would never agree on it
But the Yemenis one of those places where external cash (altho always welcome) is not a real driver - it is Family, Village, tribe & country.... and religion a long way after that
As they are all armed they just need to get together and you have a significant force. Generally speaking outsiders who have tried to meddle have regretted it
Tho' TBH I've always found them very pleasant people - but I've never been on the wrong side of them