State Dept. Spox on ISIS: “We CANNOT win this war by killing them
It worked with the Germans and the Japanese in WW2.
We would need to fight similarly to how we fought in WW2. Not with current "Rules of Engagement". We would have to kill a sufficient number of millions (to include their women and children as well), that for generations afterwards they would have no stomach for trying to take us on again.
Machiavelli once said "Do not do your enemy a small injury", by which he meant "Don't hurt your enemy just enough to piss him off, while not impacting his ability nor desire to continue to fight you." We have been doing nothing but inflicting "small injuries". We need to go after the wealthy Arabs who finance global jihad.
Sadly, any lessons from WWII would be lost on our modern State Dept. They are convinced that they KNOW BETTER than the racists and neanderthals who won that war.