Let's not forget that when the UN made Israel a Jewish state, a lot of the Palestinians left on the advice of their Muslim neighbors. It was the thought that if Palestinians left the country, a lot of the infrastructure such as farming, would go by the wayside. It is tough to operate a country when most of its population leaves.
But the Palestinians were treated like garbage by their muslim neighbors, and tried to move back. Its like quitting your job when the company is under new management, and demanding it back 2 years later because the new company buried you in the mail room.
I agree with the others that this is conflict that has ensued for thousands of years where the Jewish people received ill treatment from Greeks, Romans, Christians, Muslims and others. And this conflict will continue on until religion dies or the human race becomes extinct. Plus, the US will never abandon Israel because it gives them a true ally in the Middle East