They were forced off their family lands.
As were the Jews, the Romans, the Sea People, the Hittites, etc. before them. Land ownership comes from improving the land and then defending those improvements. The "Palestinians" did neither. In pre-1948 Palestine, a person with "Palestinian" on their passport could have equally been Jewish, Arab, or Christian in some version or another. You don't know your history.
our arguments about Israel improving the lives of the Palestinians
That's not what I said. What I said was that the only free Arab is one living in Israel. Gaza and the West Bank are not Israel, nor are the people there free. But that is in large part because of two things: 1) The rest of the Arab world refuses to step up and help their own fellow tribesmen. Palestinians are most closely related to Jordanian Hashemites, but neither Jordan nor anyone else has stepped up to help them all that much. Why? Because of 2) The awful behavior of the Palestinians. They are the ghetto trash of the region. Israel repeated has offered them more than fair terms to calm things down. What do the Palestinians do? Elect Hamas, launch rockets, make war purposefully on civilians with the intent of killing innocents. NO one wants them around, and for good reason.
After all, when was the last time the Apache tribes went to war with each other?
Again, you don't know your history. The Amer-Indians were vicious to each other, as even a causal reading of the history of the Plains Indians reveals. This "White man bad, Indian good" narrative rolls of the lips of ill educated lefties who think Zinn was a historian, but - while true in part - it missed the context and bad behavior of the people being "expelled"
insult the intelligence of those whose opinions are different from yours
I insult people who don't know what they're talking about but act as if they have the last word. I'm sure you're not dumb, but you're so deeply dipped in the lying in misdirection of the progressive left, and have been so very badly educated, you're incapable of grasping the much larger discussion here and the many nuances involved. I don't think Israel is always right, I just think the Arabs and Persians are pretty much always wrong. In that context, I mostly side with Israel.
Go read a book. I recommend you read the one below. Even the Arabs - who cannot stand Netanyahu and Likud -agree that the beginning chapters of this book is a very fair and clear explanation of the beef. The later chapters will help you actually understand the Zionist position and why it is viable and arguably absolutely necessary:
http://www.amazon.com/Place-Among-Nations-Benjamin-Netanyahu/dp/0553089749