The way you’re talking it’s as though he shot those kids himself. He’s not responsible for the fact that people can so ridiculously easily get hold of the weapons to do this. That’s the only “disgrace to humanity” here. And it will be the next time. And the time after that. And the next fifty times.
If he’d gone in alone, armed with a pistol and no body armor, perhaps he’d be a hero, probably a dead one. I don’t think not acting heroically makes you a disgrace or a coward. It just makes you a normal human being. Nobody should be required or expected to undertake a suicide mission as part of their job.
“Our cops aren’t brave enough” is not the problem. But I suppose it’s yet another way to distract from the real issue.