Technically, I suppose you could call this a "reaction." It's probably more accurate, however, to say that the man in this photograph is acting in front of the cameras. Without the ever-present photographers situated ever-so-conveniently on the hospital stoop, one would imagine that this man would feel no need to parade his emotions so openly.
Of course, it's pictures like this that remind us exactly why it is that we don't need the army of photographers on the ground in Gaza.
A Palestinian man reacts as he holds a blood stained sheet at the entrance to Shifa Hospital in Gaza City, Thursday, Jan. 15, 2009. Israeli forces shelled the United Nations headquarters in the Gaza Strip on Thursday, setting the compound on fire as U.N. chief Ban Ki-moon was in the area on a mission to end Israel's devastating offensive against the territory's Hamas rulers. (AP Photo/Thaer Al-Hasani)