In my humble point of view, the best thing each and every one of us can do in response, is pay our respects for the losses, yet not ponder long on the horrific stuff. Instead I suggest we gotta turn that terrible energy around.
How? Aside from getting actively involved in the Causes that want to repair the world. . . The way I see it is like this:
If we take time to go into silence and reflect more on the goodness we have experienced in our lives, and are grateful for every little and big thing we are allowed to enjoy on this magnificent planet, we send a better energy through the ether. And if we encourage all those we come in contact with, to get out of their emotional commotion and do the same, now we got a movement going on.
You may accuse me of wearing rose-colored glasses, that's ok. Everyone's reality is different. According to quantum science we all create our own reality . . . and mine is - PINK :-)
So I invite you to get on my bandwagon and send out the good pink fluffy feelings - the feelings that warm your heart and calm your mind. Create the butterfly effect. Get those good vibes circulating around the globe.