Three true experts have posted in this thread, and these are the folks whose opinions I would respect most.
1) A man who jumped/fell off a roof at work, from roughly the same distance, and broke bones doing it.
2) A man who has been to Africa and has seen how Painted Dogs take down their prey -- how quickly it happens, how violent it is, and how difficult it would be to get a fast shot if one were in the midst of it.
3) A man with a doctorate in psychology, talking about survivor guilt, PTSD issues, and realism avoidance in planning.
We live in the age of the instant expert, where everyone's opinion is as good as anyone else's, and the guy who shouts the loudest usually "wins" an all-too-often adversarial online conversation. But I tend to listen hardest for the voices of people who have in some way been there. I might not like what they have to say, but darn sure I'll listen to it. To my ear, a loud voice cannot compete with a clear voice, even if it's a whisper.
Speaking of loud voices, there sure seems to be a lot of emotionalism in the thread. I'll grant it's an emotional topic, but it's hardly helpful to be nasty to each other over it.
Would I stand by and "let" the baby get mauled? Nope. If I were close enough to act, I would immediately choose one animal from the pack, and shoot that animal at the base of the skull if possible -- or in the spine near the hindquarters if not. Then I would choose another animal and do the same again. If the animals ran away at the first "warning shot" that incidentally dropped one of their packmates, that would be good. If they didn't, I would keep going until I ran out of ammunition or until it was plainly too late to save the child. (None of this is chest-beating, Glenn; I have the physical skills to do it and have thought through wild animal attacks as we live in a rural area where there were some feral dog packs near my home when the children were younger. There's nothing unrealistic about having a plan to act in a generalized set of circumstances, or about knowing your own shooting skills well enough to know whether you could carry it off under stress.)
Incidentally, for those who are saying that bystanders couldn't tell for sure that the child was actually dead, um, no. We have not seen any pictures of this child's injuries (nor do we want to!!), but .... dogs often go for the throat. If the child's head was completely severed, as seems not unlikely, or if the dogs literally tore the child's body in two, even a non medical person might take that as A Clue. Even if it was less clear than that, I would not want to take away a survivor's coping mechanism. The people who were there need to believe that nothing they could have done would have saved the child. The factual or non-factual nature of their belief hardly matters to us at this point, but it could be a sanity saver for them. Let it be.
My personal website: Cornered Cat