The big difference is that AQ is located in 60 different countries. There will be no negotiated settlement on the USS Missouri. We didn’t have to kill most of the Japanese or Germans to win WWII. In this one, we will have to wipe these vermin off of the face of the earth.
We killed enough to defang them as a viable threat. You’re right, with a mobile address, as a percentage we’ll have to kill lots more, or convince the nations harboring them to do the job for us. While I appreciate the sentiment, we won’t be able to wipe radical Islam off the face of the earth, it will reappear periodically.