First of all, the 12-year-old was not a thug, he was a kid among other kids.
Secondly, the boy may have pulled the BB gun from his waistband but he did not point it at the rookie.
Thirdly, the rookie cops had their guns drawn, pointed at the boy, with their fingers on the trigger. They had the advantage. There was more then enough opportunity to challenge the boy with secondary verbal warnings to lower the BB gun.
Very interesting that you would side with thug rookie cops who are more than willing to shoot a child without trying to defuse a situation. Someday you may be the one in a rookie cop's sights and you will feel very differently. However, you won't look like a 12-year-old. Cops are too militaristic and too trigger-happy, and will do Obama's bidding without hesitation as he destroys our rights.
You see a little boy who had potential. I see a young thug who was acting in a thuggish manner: (1) brought a gun to a rec center, (2) hid the gun in his waistband when the cop showed up, and (3) pulled the gun out of his waistband when told to raise his hands. I don't know how good the kid was with a gun, and I don't want to find out. Neither did the cop. Given how many people can reliably put a round in the black at 25 feet in under a second, plus the change that a beginner could put a round in the black (the cop or a bystander) by luck just as fast, I'm okay with the cop shooting in that situation.