Since there will probably always be rebels, it may be a good thing to give them a focus that makes it easier for the powers that be to locate and target. In other words, keeping OBL around may be a good thing because at least we have an idea where the threat comes from -- he and AQ will draw the bulk of the malcontents who desire to disrupt the status quo.
Excellent point, perhaps more so when looking at our surreptitious collections effort. "he must take these to brother Osama" must make for a decent spike to orient on.