To state that Hamas usues itas own people as a shield is pointless because so does everyone else. In every conflict since ww1 more civillians have died in any given conflict more than combatents.
The Israel Palestinian conflict will always continue whilst one takes land from the other. People have a right to fight for their homes, freedom and liberty. Israel and the Israeli population are not fighting the same fight, they have their land and homes and seek to expand same all the time. Its a simple fact that when you displace a population conflict follows closely.
Isreal has a right to defend itself against any kind of attack but so does every other nation and peoples. Israel is not any different than anyone else. The only difference is that Israel has a strong military and is backed by the US where as the Palestinians are the opposite of that. It would be interesting indeed is a capable military power decided to back and help the Palestinians as the US does with Israel. It would be interesting then to see how Israel would handle that situation.
Needless to say this conflcit will not end till one destroys the other, the question is would the ultimate destruction of the palestinian people mean the destruction of Israel. Meaning are Israels actions sowing the seeds of their own destruction as the more enemies it makes the greater the chance it will design its own downfall.
Historically nations that have waged war for whatever reason have eventually collapsed themselves either financially or through being destroyed by conflict or both.