Yes, arguable. We were all blind to many possibilities. On Arafat and the PLO I definitely agree. The Reagan administration did not do enough there either.
Jim, although I don't entirely disagree with your premise regarding Reagan, it's impossible to dismiss the cold war situation at that time. The void left by the demise of 'the evil empire' is a lot easier filled by the U.S. today. At that time we would have had to risk confrontation to do what we're doing now.