First of all there are no such people as Palestinians. They were invented by the Soviets in Moscow in 1965 as a propaganda tool when the wrote the preamble to the PLO Constitution. The term started being used on June 4 1967
The lands which the Arabs using are not theirs. Since early in the 20th century they have refused it.
In 1947 the UN passed Resolution 181 dividing the land between Jews& Arabs. Jews accepted. Arabs refused. Then lost it completely in 1949 when 7 Arab nations attacked the fledgling State of Israel.
Since then they have had many offers & refused.
Judaea & Samaria which we are building on has been the Jewish land for 4,500.
Check the Oslo Accords & you will see Israel is building legally