Sit and watch the site run thru the full timeline. Every single red dot is an attempt at, if not successful act of, mass murder. It's a powerful message. Retaliation is inevitable, casualties unavoidable. So long as some Gaza residents keep shooting indiscriminately at their neighbor, regardless of any/all attempts at polite reconciliation, and other Gaza residents do not make serious attempts at stopping their fellow residents from such violent behavior, and the "police" (UN et al) will do nothing, the neighbor has no option but to violently eradicate the attackers thru a less-than-precision process. Gaza may have legitimate grievances, but indiscriminate shooting at innocents isn't a tolerable way to address them.

"Reflective contemplation is not required in the presence of an upraised knife."

It sounds like you're applying journalistic standards to this site. There is no obligation to tell both sides of the story here; it's just a neat visualization, useful as an aid to other pieces of journalism which don't contain such information.

I have trouble feeling bad for Gaza when they throw the first punch. If I threw rocks at my neighbor's house, I shouldn't be surprised when they retaliate.

What if your neighbour had moved into your house uninvited?