The next few months
Imagine the international armies (UN or others) begin tocamp in Afghanistan; winter is tough and the situation gets worse. the Taliban keep fighting (guerilla-like) and then, in february or march, a well aimed number of attacks lead to the deat of dozens of soldiers from the UN. Within a few days, the international community's unanimity will collapse and we'll leave Kabul the same way we left Libanon, Somalia or Rwanda.
I'm afraid the end of OBL or Al Qaeda won't mean the end of islamic terrorism.
Raoul