I believe that the Isrealis are as guilty of the Palestinians if not more in this whole conflict, but Darin is right, you have to look at Arafats whole history, not just the past 5 years or so (Sharon's as well for that matter).
Arafat was as bad as any of the butchers that we decry today, he has somehow gained legitimacy (some) in the past few years, but his past will always be there.