What Hamas is doing now is unacceptable.
What Israel has been doing to the Palestinian people for decades is equally unacceptable.
The land under dispute has been settled by both Jewish and Arabic peoples since the late Stone Age - the archaeological evidence is pretty clear on that.
In an ideal world, both sides would get together and sort it out. Unfortunately the creation of the state of Israel put paid to that - not because it happened at all, but because the interests of local Palestinians were completely ignored at the time.
The roots of this lie in the past, there isn't an easy fix and right now the victims are ordinary Israelis and ordinary Palestinians.