I think you forgot a teeny-weeny bit of history here. Palestinians lived in every settlement/city that is now jewish. Then the jews came from Poland, Russia, USA, Italy, etc etc and immigrated to a country they never ever had sat their foot on, and had no legal claim to. More and more came, and those who already lived there obviously disagreed and they protested like any normal person would do.
Who knows who started, but there were some terrorist incidents from both sides in the late 20's, and many different jewish terror organisations were formed and slaugthered both palestinians and british. They terrorized the entire region. They even offered to fight alongside with the NAZI's against the british.
This kept on till the UN decided to make Israel and Palestine, but this wasn't enough for the jews and they grabbed 24% extra land. In doing this, the jews tried to ethnically cleanse the land of palestinians, and they butchered entire villages and made hundreds of thousands of ppl flee from their land.
NO ONE will accept to loose their land like that, and they had the support of the Arab nations and war was declared. However, Israel was much stronger than ppl thought and Israel grabbed even more land.
Even Switzerland would go to war if someone one day came in and grabbed most of their land, and threw the swiss out.
NO ONE would stand still and NOT declare war.
The jews STOLE land to create Israel. And have since that ethnically cleansed more and more land, and kept the palestinians in a prison with no rights. And therefore the palestinians have EVERY right to fight back.
Today, even more children got killed btw.
Hamas has killed 5 ppl in total, while Israel killed 520+ and injured thousands. 46% of all injured are women/children. This shows how little the israelis care about avoiding civilian casualties. They couldn't care less about them.
This is the very same retoric terror organisations use, those civilians protect and support their enemy, so they must die.
So how can anyone now say terror organisations are wrong to bomb civilians when Israel is allowed to do it?