First, that first knife is a beauty - a real camp knife -- even a hint of a long Nessie. He should be a proud Eagle to carry that fine knife.
As for Scouts and knives, this is not a "liberal"/"conservative" thing. (Although, how anyone can call Scouts "liberal," given the present meaning typically given that word, is beyond me.)
It's an ignorant/knowledgeable thing. Our society has changed. There are few handtool users around. Perfectly normal tools look alien and dangerous to the ignorant. I mean, did you even look at a sickle?

A SWORD



(Woops. Corn Knife

)?
Local Councils and units absolutely can ban fixed-blade knives. Many have done so. It is theor right under Scouting bylaws. If you do not agree, work to change the rule or go elsewhere. A Scout is Obedient.
AustenTXShooter is on the track: BSA policy "discourages" "large sheath knives" on the grounds of utility in the Scouting program. Meanwhile, BSA sells 8 "kitchen" knives. No prohibition. No mention of safety. Not to mention the continued sponsorship of the use of axes, a far more dangerous tool.
When one asks those responsible for banning all fixed-blade knives why they adopt that rule, they always mention "safety." (Most Councils that ban "all" fixed-blade knives still sell those 8" kitchen knives, by the way. Check into that mmmotorcycle.)
I then ask these men if they expect boys will encounter fixed-blade knives. They say, "yes." Then I ask them how the boys are to learn safe use of such "tools" (Always call them tools.) and if we are missing an opportunity. I point out the actual BSA policy (They seldom have any idea what it is, urban legends having replaced much knowledge.) I show them a Bark River Mini and a Lone Wolf Ranger, the one banned and the other allowed as a folding knife. "Where's the logic," I ask.
At the least, I leave them unsettled.
I offer to address their unit Commitee or Council Executive Board.
Above all, I remain calm.
How to insure safe usage? It is actually easy, as James61 knows. It is part of what Scouting is SUPPOSED to be - boy led. It's not one - or ten - adults watching. It's ALL the Scouts watching, and they are FAR tougher than the adults. (Kids tend to see black and white, not gray.) We have had one troublesome incident in the last twenty years (The kid had to go.). "Rat on Your Buddy Week" is 52 eeks a year when it comes to Tot'N'Chip. That method has worked for nearly a century, but does not work when it is not even tried.
If you are involved in Scouting, do not leave the field to the ignorant. I have sucessfully had bans dropped at two Scout camps. I, and others, prevented our Council from adopting a ban.
Or you can haul out "sheeple," etc. and piss everyone off.