O'Reilly was incensed that it "puts our troops at risk". Clark responded that what's putting the troops at risk is the chain of command letting, or even making, this happen in the first place.
O'Lielly was saying that it happens just like this in every war, with Clark rebutting that those were isolated incidents which were court-martialed.
And then, this:
Clark: And let me explain something. You go all the way up the chain of command ...
O'Reilly: General! You need to look at the Malmedy massacre in World War Two, and the 82nd Airborne who did it!
Video of the exchange here.
The Malmedy massacre? Well, about that on the flip...
On December 17, 1944, near the hamlet of Baugnez on the height half-way between the town of Malmédy and Ligneuville in Belgium, elements of Waffen-SS Kampfgruppe Peiper encountered the American 285th Field Artillery Observation Battalion. After a brief battle, the Americans surrendered. About 150 of the prisoners of war were disarmed and sent to stand in a field near the crossroads. Peiper and his leading armoured units then continued their advance.
A tank pulled up, and a truck shortly thereafter. A single SS officer pulled out a pistol and shot a medical officer standing in the front row, and then shot the man standing next to the medical officer. Other soldiers joined in with machine guns. It is not known why this happened; there is no record of an order by an SS officer. While the shooting of POWs was common on the Eastern front, such incidents were rare on the Western front.
Another good account: History Net (w/ thanks to AaronBa).
Why do Bill O'Reilly and Fox News believe that American troops used to behave, and ought to behave now, like Nazis?