TM7, 50m in military parlayance is 50 meters. Kill radius is the radius of a cone or sphere originating at the point of impact. So an unguided rocket fired into a population center with the capability to kill anything within 50m, regardless of whether the land is legal in dispute or not, is irresponsible. You did point out unguided, whereas the Israelis used guided munitions and from the reports even from Al Jazeera, only 3 received minor injuries. Judging from the volume of fire, that's pretty impressive controlled fire. From a US military standpoint, we would say that was a judicious use of fire in that it destroyed the targets with very minimal collateral damage. Notice also that the targets were specific to rocket capacity - the Israelis did not target population centers, or foreign visitors. They target the means to manufacture the rockets themselves. Again, judicious use of force, or a measured response.
I will concur that the land in question is in legal dispute. Imagine you and I had large farms that bordered each other and we had a boundary dispute. You and your family decided to picnic in that part of the area that was in dispute, and I lobbed a grenade into your midst. That is a separate criminal act, apart from the dispute, and the dispute itself is not just cause for the action.
