It took 14 years, but now we have an answer.
It was March 2003, the invasion of Iraq was underway, and Major General David Petraeus was in command of the 101st Airborne Division heading for the Iraqi capital, Baghdad. Rick Atkinson, Washington Post journalist and military historian, was accompanying him. Six days into a lightning campaign, his division suddenly found itself stopped 30 miles southwest of the city of Najaf by terrible weather, including a blinding dust storm, and the unexpectedly “fanatical” attacks of Iraqi irregulars. At that moment, Atkinson reported,
“[Petraeus] hooked his thumbs into his flak vest and adjusted the weight on his shoulders. ‘Tell me how this ends,’ he said. ‘Eight years and eight divisions?’ The allusion was to advice supposedly given the White House in the early 1950s by a senior Army strategist upon being asked what it would take to prop up French forces in South Vietnam. Petraeus’s grin suggested the comment was more droll quip than historical assertion.”
Certainly, Petraeus knew his history when it came to American interventions in distant lands. He had entered West Point just as the American war in Vietnam was beginning to wind down and did his doctoral dissertation at Princeton in 1987 on that conflict (“The American Military and the Lessons of Vietnam: A Study of Military Influence and the Use of Force in the Post-Vietnam Era”).