Sadly, the logic "if we make it illegal they won't do it" is all too prevalent today. Nor will it go away any time soon.
There's an old saying: When guns are outlawed, only outlaws will have guns.
Crime cannot be prevented, only discouraged and punished. There will always be tragedies like this, even if the most stringent laws are enacted. Sad fact.
Burying our heads in the sand and saying "if we get rid of X, crimes like this won't happen" simply isn't true.