In early 1965 the United States unleashed the largest sustained aerial bombing campaign since World War II, against North Vietnam. Through an ever escalating onslaught of destruction, Operation Rolling Thunder intended to signal America's unwavering commitment to its South Vietnamese ally in the face of continued North Vietnamese aggression, break Hanoi's political will to prosecute the war, and bring about a negotiated settlement to the conflict. It was not to be. Against the backdrop of the Cold War and fears of widening the conflict into a global confrontation, Washington policy makers micromanaged and mismanaged the air campaign and increasingly muddled strategic objectives and operational methods that ultimately sowed the seeds of failure, despite the heroic sacrifices by U.S. Air Force and Navy pilots and crews Despite flying some 306,000 combat sorties and dropping 864,000 tons of ordnance on North Vietnam - 42 per cent more than that used in the Pacific theater during World War II - Operation Rolling Thunder failed to drive Hanoi decisively to the negotiating table and end the war. That would take another four years and another air campaign. But by building on the hard earned political and military lessons of the past, the Nixon Administration and American military commanders would get another chance to prove themselves when they implemented operations Linebacker I and II in May and December 1972\. And this time the results would be vastly different.