Charles Durning played a WWII vet in the NCIS episode "Call Of Silence". He played a Medal Of Honor recipient who claims he killed his best friend "Wade" in combat on the Sulphur Island.
He is about to be arrested in one scene by two Marine guards, when one of the NCIS members pulls back Durning's jacket, revealing the medal. The guards immediately snap to attention. It was the most well acted episode of the entire series, leaving me nearly in tears.
RIP Mr. Durning.