In the first, Benny Morris begins his talk with a discussion of the controversy regarding refugee numbers and the way the Palestinian Arab refugee issue has escalated over time.
In the second (which is especially worth looking at) he describes the four stages in the genesis of the Palestininian Arab refugee problem. It will be seen that voluntary flight by the Arabs rather than deliberate expulsion by the Jews was the dominant factor in the creation of the problem. He also shows that the actions of the Israelis towards the Palestinian Arabs were motivated by the fact that the Arab nations wished to destroy the State of Israel and simply wouldn't compromise.
In the third he examines the absence of a coherent policy on the part of the Arab leadership regarding evacuation. He puts into context the atrocities that occurred on both sides. And he discusses the reasons for the perpetuation of the refugee problem, a discussion that continues into the fourth video.
Hat tip: AustralianNeoCons