In an attempt to clarify...
Explaining what one means can occasionally present some difficulties. This is particularly true in spontaneously written communications. The words we choose in those explanations can frequently distort the message received by others, either because those words were poorly chosen, or because the reader's frame of reference and/or worldview differs significantly from that of the writer.
I think what the several members are trying to say about the Aurora massacre is that the folks that are peripherally involved in supplying Holmes with his equipment - especially the firearms - are naturally feeling some degree of emotional upset over the misuse of those guns. This upset does not necessarily have to be "guilt", nor does it have to be overwhelming. IMHO, the emotional reactions probably ran somewhere between "Oh, s**t!! I sold that to him! Oh, well... what's for dinner, baby?", to (perhaps) some undeserved entry-level, nagging (but short-term) "guilt". The emotional reactions to this thread seem fairly wide-spread, especially when it comes to the non-accusations. Emotional reactions are individual-specific.
Emotional reactions to a specific incident are not universally shared by the observers of the incident. Some will have the same reaction (as during the Twin Towers incident - the vast majority were appalled), yet there were a few who thought those 3,000+ people deserved to die simply for being there. But, no matter how inappropriate the reaction may seem to others, whatever emotion one experiences is valid... at least for that individual. Just sayin'. Pax...
:shocker: