You are seeing and living the results of why.
There is no civilian incident to date that could not be easily handled with civilian only weapons. Police should have Ruger Mini 14 rifles and 12 gauge pump shotguns. Most importantly they have radios that can call in virtually limitless numbers of more cops. AR15's are military weapons in civilian legal form. The police are NOT the military. Dress like a soldier, act like a soldier. Train like a Soldier, fight like a soldier. Cops are NOT soldiers.
Our country got along just fine for 200 years without SWAT teams. They are a menace to our free society and need to be gone. Ninety nine percent of the time SWAT teams are used as show of force. They show up after an event has taken place to show off their MILITARY full auto weapons, Battle Dress Uniforms and other military toys. There is no incident that cannot be handled by normal peace officers who dress and act as cops.
So, they should not have AR's, but can have a mini-14. Can you expand on the difference in ammunition, rate of fire, muzzle velocity, magazine capacity and reload time difference between these 2 popular platforms?
“AR15’s are military weapons in civilian legal form.”
There is a lot of difference between automatic weapons (Military) and semi-automatic weapons (civilian).
Since the police are not military, they must be civilians, right? And as you noted, the AR15 is a civilian-form rifle. So, why shouldnt they have AR15s?
Obviously an AR patten rifle is more ergonomic to most people than a Mini14 and the action is less prone to problems,, but the caliber and firepower of the two are equivalent. If you dont think cops should have AR15s, you shouldnt be suggesting they have access to Mini14s either.
Most importantly they have radios that can call in virtually limitless numbers of more cops..
And I dont know where you live, but in my neck of the woods there isnt an unlimited supply of police officers twiddling their thumbs waiting to be called if a serious incident happens. It makes far more sense to have a small number of officers specifically trained and armed to handle bad situations (IE a SWAT team) than to think you can pull officers off patrol, traffic, and responding to other calls, to respond to one bad incident that in your ideal world they arent equipped for anyway.
There is no incident that cannot be handled by normal peace officers who dress and act as cops.
Again, one of the reasons SWAT teams and heavier weapons for cops started to happen was because of a growing number of incidents in the 70s, 80s, 90s that couldnt be handled by patrolmen armed with revolvers.