Kyle put himself in the position.
Anyone who has a clue in owning a gun (pistol, rifle, shotgun, etc.) knows that the best thing to do is avoid the fight. Kyle is a wannabe cop who went and voluntarily put himself in the thick of it.
No one hired him. no one asked him.
How many of his Kenosha-based family members were out protecting a used car lot?
The big picture is that he did the wrong thing, even if the law absolves him of guilt. if not now, he will eventually understand that three people are dead at his hand. Three people who may have lived to a ripe old age if not for his trying to play policeman.
If it doesn't weigh heavily on his conscience now or ever, then he is a sociopath.