The "Old Yeller" lesson
A lot of people have been knocking around the concept that the CIA or other spooky organization basically "created" Bin Laden, so this is all our fault, and we have no moral authority to go after him with the military.
On the contrary, if we did in point of fact "create" him, it is even more undeniably our responsibility to take him out.
If he gets rabid, you shoot your own dog.