Why should we be surprised? The Palestinians celebrated in the streets when the twin towers fell. Palestinian arabs dealt in terror even before they had invented their nationality (Jordan was broken off by the British from mandatory Palestine in 1922 and it is there that palestinian national aspirations lie. The land west of the Jordan was intended for the jewish state and if only for security reasons must remain so).
In the days when 'palestinian' referred to jews living in the Land of Israel arabs living there never ceased their terror against jews. They were also less mealy mouthed then, claiming proudly that they had killed jews. It's only nowadays that they euphemistically refer to 'zionists' when they fire rockets indiscriminately at Israel. Their recent successes were the murder of a teenager after his school bus was hit by an anti-tank rocket. Last year a Thai worker was killed on a farm.
Arab terror in Israel dates back to the turn of the 20th century with the murder of jews peacefully farming their lands. In 1929 the jews of Safed and Hebron were massacred by their neighbours with whom they had thought they were on good terms. The jews living in those communities were not even zionists but traditional orthodox jews. This gives the lie that the arab hatred is for Israel and zionism rather than good old fashioned anti-semitism.
So just as the Palestinians celebrated the horrors of the twin towers and are al Qaida's most avid supporters ,Gaza is grieving today on the news of Bin Ladens death. The West should take note. A palestinian state is just another islamist waypost on the way to the caliphate.