I was in kindergarten when the Challenger exploded. Strangely enough, aside from the subsequent media coverage and video replays of the disaster, the most prominent memory I have of the event is the school's principal on the intercom. He announced, "The Challenger HAS exploded." I suppose he was addressing chatter, since there weren't enough televisions for every class to have seen the broadcast.
The fatality rate of humans in spaceflight isn't one I would take comfort in for an airline. However, considering the mechanics of launching humans into space from Earth's surface — a massive amount liquid fuel igniting to the tune of several million Newtons — not to mention constant logistical concerns upon concerns, NASA actually has a remarkable safety record. And it's not just NASA. Several Soviet/Russian cosmonauts have died in missions and training also, and one Israeli died in the Columbia diaster. In total, human space programs have so far seen 18 mission-related fatalities, as well as several deaths during training and numerous non-fatal accidents. Depending on who you count, that's 18 out of 430 humans in space being killed, or about 4.2% over half a century (slightly higher if you count the Apollo 1 launchpad fire).
Such tragedies are just one price of braving the wild frontier of space. It isn't unlike other frontiers, in that regard, such as the oceans and the New World. I wonder how many explorers died at sea in the 15th Century? Without people willing to risk life and limb, the spectrum of progress available to our species narrows significantly.