All this was started by Rosenbaum, not Kyle. Have you seen videos of Rosenbaum the day of the shooting? Rosenbaum was hyperaggressive and acting out in a violent manner, including trying to set fires and throwing rocks. Rosenbaum was a menace to society.
Grosskreutz was in the wrong for pulling his gun, because Kyle had just been chased by, and had just had to defend himself against an enraged Rosenbaum. Grosskreutz made a mistake in accessing the situation, pulled his gun with the intent of using it, and paid a heavy price for it (his arm-wrestling days are now behind him).
The other one was trying to bash Kyle’s head with the edge of a heavy skateboard.
All three men shot were trying to harm Kyle, and he defended himself. It’s been proven in a court of law.
Thank God in the United States of America that we still have the right to defend ourselves.