I rarely cry from things like this which are, at least physically, removed from me. But my eyes have been welling up on and off throughout the day. Thinking of the Christmas presents that will never be opened. Seeing the flags lowered. Thinking of all those teacher who, at some point in the future, are going to have to walk back through those school doors.
We had a school shooting in our elementary school six years ago or so. My mother was there, and we lost a good family friend. But there were no children involved, since it was an inservice day. Even so, with "only" two adult deaths, I've watched many of the teachers we know struggle to make themselves go on. I can not fathom the exponential increase in grief with so many young lives lost.
My heart aches for everyone touched by this, which is everyone.