It's a straightforward case of a police officer placing himself in danger, and then using deadly force to extricate himself from the danger.
If this were an altercation between three civilians which ended in the death of one of them, with all actions being exactly as recorded on the videos, someone would be on trial for murder. Since police are allowed to act in this way, the Attorney General has declined to press charges. There is nothing correct here.
It's a failure of police training and policy. Whether anyone is held accountable for this death, remains to be seen.
One thing is certain. In a society such as ours, where guns are easy to obtain, and anyone is likely to have a gun, it does not make a policeman one bit safer, if the public believes a policeman will shoot first and ask questions later.