Your questions:
1) Arguing the NRA and the gun lobbies aren't powerful seems patentably false. When they say jump, Republican law makers ask how hi. If they aren't influencial, why does every important Republican try to take pics with Wayne Lapierre?
2) See answer to 1). If NRA is influential, then we do care what they think.
3) Deer rifle - 30-06 or 30-30 caliber rounds, typically 3-5 round capacity
AR-15 - .223 caliber, magazines can hold up to 100 rounds though most high capacity magazines don't hold this amount.
And the question and answer to 3) is my whole point. Most of these mass shootings would result in far lower numbers of dead and injured if the perpetrator didn't have assault rifles with high capacity magazines.
Think about that shooter in Vegas at the concert a few years ago. Over 50 dead. Multiple high capacity magazines and assault rifles.
My opinion is that, at a minimum, we should have some restrictions. Perhaps a special vetting before someone is allowed to go purchase these guns that can do so much damage. Or perhaps a limit on magazine sizes without a special license.
In the last two weeks, we have had two 18 year old kids with undeveloped frontal lobes go buy assault rifles and then attack innocent people. The one in Uvalde had superior firepower and protection to the armed guards and was able to shoot them and then enter the school. These ARs with high count magazines are simply too easy to get. As long as we don't limit access to these weapons, we will continue to have mass shootings with higher numbers of casualties. If we don't reduce access to ARs with high capacity magazines, we will have many deaths, including children, that could have been avoided.
Years ago I came on here after a school shooting and went into great detail about how difficult it is for the untrained to track and engage targets. A shooter wanting to inflict maximum casualties would do what the NZ mosque shooter did.
12 guage Beneli with 13 round extended tube and buckshot. Humans, when they're afraid in a contained area, huddle together like quail. One blast from buckshot hits several targets. With an AR, you've got to engage each target separately. Through and through wounds don't always happen.
Your AR (not an assault rifle) is not a close range weapon-- it's a stand off weapon. Yes, it can be used effectively AT close range, but it takes discipline and training. In this event, the first officers engaged had side arms-- this meant the assailant had fire superiority capability. He could engage the officers at distance and with more accuracy than their Glocks could.
However, put everybody in a phone booth, and that long rifle loses its handling.
I get your stance-- "make every weapon a single shot weapon with no magazine and fewer people will die." Logical-- yes. Reasonable-- maybe. Actual-- never going to happen.
As far as the NRA goes, it's a shadow of its former self. I left years ago. Why?
Because I don't need a lobbying organization to protect an unalienable right that was given to me.
Now, may be talk about those "undeveloped frontal lobes" you referenced. Taking hormones and/or lopping of your punishment or getting boobs bolted on so you can identify as a female-- there's tons of kids doing this and folks (perhaps like you) defend that.
Let's talk about Vegas. Thos weapons were semi-auto rifles that had been augmented. They were not full auto. Simply "rigged" to be "like" a full auto.
And as far as restrictions-- we have them. This kid, just like I did myself, bought his rifle legally-- with a background check and everything.
Now please explain how we should do a "double background check". You are either a criminal, or you aren't. If you are a criminal, you can not buy a gun. If you're not, you can.