Here's a different kind of question I've often had about large scale tragedies like natural disasters, diseases & gun violence:
We get so caught up in the emotion of the violence that we don't consider the long-term, historical consequences. To put it bluntly: the planet is overpopulated already. Maybe we shouldn't try to cure every disease, we shouldn't confiscate all the harmful drugs, etc. Perhaps we'd be happier if we made peace with the fact that rabid animals are going to dwindle the herd from time to time (as they have in much greater volume throughout history) & that's not really a bad thing in the long run. Should we try to stop as many large scale attacks as possible? Of course... but I don't think the zeitgeist should have an aneurysm every time one occurs either. I think we be served to draw some historical perspective on how difficult the human condition has always been & how that is something of a blessing in disguise.
Take for instance how valuable the conquerors throughout history, as bloody & awful as they were during their reigns, have been to population control. We think the planet is overpopulated now: the environment sick, the resources dwindling; where in the world we be without Genghis Khan, Alexander the Great, Napoleon, Julius Caesar or for that matter the bubonic plague, cancer & AIDS?
Here's an article on the beneficial impact Genghis Khan's conquests had on the environment & sustainability, for example. There are already 7.125 BILLION people on Planet Earth. Try to extrapolate out how many people would be here now if EVERYONE had survived & had kids, which seems to be the ultimate aim of modern society... a right if you will... to defy the boundaries of nature. It'd be one hell of a dystopian nightmare that's for sure.