Norfolk, I agree with your last comment completely. I think we'd be looking at a very different Jordan today. Where we probably disagree is that I think there is a strong case to be made that the benefits of an annexed and secure West Bank would outweigh the cost of a hostile Jordan.

Rex, I'm aware of the difficulties Jordanian armor had, particularly in Amman. It's one of those textbook cases on using heavy armor in built-up areas. I'm unconvinced that additional refugees would have changed the basic calculus of the situation though. Frankly, in the aftermath of 1967 I think the Arabs would have expected Israel to expel the Palestinians from the West Bank -- the Jordanians did after all expel Jews from East Jerusalem, and Jews were not really welcome in much of the arab world after 1948.

I think the really interesting thing about the Jordanian-Palestinian fight is the effect IAF overflights of PLA columns must have had on Syria's decision-makers, especially with the IAF's performance in 1967 such a recent memory. With regard to what you said, I don't think the IAF had to take on the Syrians, the mere threat of them doing so was enough to convince the Syrians that it wasn't worth committing their rebuilt air force to a fight they must have been sure they couldn't win.