I am biased. I believe that guns are a very useful tool that can be used for protection (and they can be "fun", too). However, as with any advanced piece of machinery, they require proper training and understanding before they should be used.

You wouldn't intentionally allow a 5 year old to operate a band saw without safety equipment and training first, right? (Hint, the answer should be "no") The same goes for a gun. You shouldn't let an untrained individual handle a deadly weapon. Motor vehicles are the same way - training and oversight are required before you can just go ahead and use an automobile!

Baldwin is irresponsible (at best) for handling the gun in the manner that he did; Prop gun or not. If the thing had a 0.0001% chance of firing a projectile at a reasonably dangerous velocity, you don't aim it at another living being unless you have the intention of causing harm.

Do I believe that he intended to cause harm? Not likely.
Did he cause harm? Yes.

Is it the gun's fault? Unequivocally, No.
Will strict gun laws solve this from ever happening again? Unequivocally, No.

/rant