The original claim was that "NATO has probably done just as much to insure peace inside it's countries as the EU has.". The counterpoint was that the Balkan wars invalidated this claim. My response was that a single war in 70 years is hardly evidence against the original claim.
They had all the resources to wreak havoc, occupy and keep hundreds of millions in factory-feudalism. They would have drafted half the world to wage their wars if necessary.
Actually history has shown that they didn't.