Why don't all members of the Air Force have to be fully qualified to be a rifleman in case of hostile events?

Most of the Air Force is "in the rear with gear" with exceptions for CCTs/PJ, and affiliated AFSC's attached to Army units, Air Ground Ops, etc. In the blue to green scenarios, the units filling those were spun up with US Army training on camps/posts/Forts doing USA small unit training and drills to do just that when they had to fulfill such missions. I would expect that to occur in future op's. There is only so much time one can take to "prepare" all personnel for their anticipated roles in the combat theaters, and this is indeed dynamic, always subject to change. We all see the view from our own tree stand, but most typically the USAF personnel who spend the greatest amount of time over enemy territory are the pilots...but their weapons are different than the grunts, unless they are shot down. As for larger crews...about the best they can do is to throw their flight lunches at the enemy.

I worked with another ground radio operator and we both received PCS orders at the same time. I went to the Middle East to a radio station at a site. We had our own weapon and we had to count and verify 120 rounds at the start of each shift (actually there were 126).
My co-worker went to Vietnam and was assigned to South Koreans on the ground as their radio operator. Long story short, he was wounded twice, saved the South Koreans and was decorated by the South Korean government and received the Air Force Cross.

I think you are in error

You're in the military

What a maroon!!!

I wasn't in the Air Force, so I'm not familiar with what they get trained on. I always figured that they had some weapons training. I can see where they might not need to qualify on m16. I do think everyone in the military should have some weapons training because it helps enforce the seriousness of the business. A lot of the of soldiers first time to ever touch a weapon is in Basic Training. I think the training could be a very good thing.

I was familiar with shooting as a kid before I joined the AF in 1956, so I promptly fell in love with the M-1 carbine, their weapon at the time. It made a polite little bang, with no recoil at all, unlike my deer rifle "Ol' Kick an' Beller".
With today's weapons, it shouldn't take any more than a couple of day's instruction to determine which end the bullet comes out of and hit a target with it. I don't think that's asking too much out of a basic training schedule. After all, don't all youngsters think they're John Wayne? Or Juanita, as the case may be?

Excellent point; especially on you rhetorical question, "ummmm why did you join the military in the first place ...?"
Being a prior crew-chief, I was well aware that a perimeter breach left is with a very short time (I think it was a matter of less than a minute) before any of us expired. Using a small tool box for cover with out the ability to return fire successfully would only serve to enhance the shooters position. That is, of course, if the airman could find the safety in the first place.
The AF doesn't necessarily need to know battle tactics, but should know how to defend themselves should the Army or Marines ability to defend the base's perimeter to full extent be comprimised.
It's happened.
If aircraft don't launch, ground pounders will be at a disadvantage. That and the enemy has our equipment. Correct me if I'm wrong, but- sans rules of engatement - in a nutshell that's all there is to it.

If you are a part of any branch of the military you should know basic Rifleman

All Air Force members, while at Basic training received weapons qualification. At least when I entered the military, that’s the way it was.