Why has the israel-palestinian dispute been one of the most long-lasting and intractable conflicts in world hi?

I need to write an essay of 2.5 pages on this question. I need 3 really good examples, one for each paragraph which should be 3/4 a page long. So far I have 1947 where the Jews kicked the Palestinians out, and the Six-day war in which Israel gained more land. Personally i dont feel thse 2 examples are very good, and i need 3, please help.