What exactly was the role of the U.S. government in the coup that overthrew Ngo Dinh Diem?” Trumbull stared for a moment at Foley’s rigid back. Then he said to Patchen, “Tell him.” “I think you already know, Paul,” Patchen said. “In simple terms, we countenanced it. We knew it was being planned. We offered advice. We provided support. We encouraged the plot. We welcomed the results.