What do you mean almost no one? The AR-15 by itself is very popular. The difference between military and civilian is one is fully automatic and the other semi automatic, that's it. Clearly having a semi auto isn't stopping the large body counts. Even so, it's easy to modify to fully automatic and there are kits available for purchase.
That's like saying their is a small difference between a civilian Toyota Camry and the NASCAR version lol. There is a monumental difference between a semi-auto and select fire fully auto.
Do you have any experience modifying semi to fully autos because you say it's easy with a nonchalance like you know what you are talking about?
You get an AR for $600. We were just talking about a few pages ago that in Arizona, Florida and other states it takes 20 minutes. No special requirements that you're talking about.
Yes you can get a civilian AR in 20 minutes.
Who needs assault rifles designed for the military? Gun enthusiasts, people who consider these their hobby. The AR-15 has been re-branded and sold as a sporting rifle. They have tournaments and games designed around the gun lol. It isn't necessary, we don't need these types of military style weapons in the hands of your every day person.
We have lots a things available to us in our modern day society that "aren't necessary." If we start defining things by their necessity we might not have very many things left.
I wish we lived in a society where there was no need for guns but unfortunately we live in world filled with humans. Why does the military need guns, why do police need guns? Most of the people that make up the armed forces and police forces are less qualified than you or I to handle such a weapon.
People use guns in these crimes because they are the easiest available option. I don't have a problem making guns harder to get, but even if we made them impossible to get, the people who are committing these terrible crimes will not be dissuaded by their inability to access guns, they will just move on to the next easiest option (explosives, pressure cooker bombs, planes, etc).
The government has failed us many times over, the FBI was monitoring the Orlando shooter, the mom of the Sandy Hook shooter tried to get him committed, many of the people who have committed these terrible crimes have done so because of our government's direct failure to stop them - even when they had the opportunity to do so.
The change needs to come from the government, its the same failure that has caused our prison population to grow out of control. The is a reactive approach rather than a proactive approach, and it has failed.