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This week, we’re excited to share a Longreads Member Exclusive from Thomas E. Ricks, whose new book is The Generals, published by The Penguin Press. Chapter 21, “The End of a War, the End of an Army,” details how the U.S. military and its leadership faltered in the final years of the Vietnam War:

“Often in warfare, it is the first year of fighting that seasons forces, which become more effective as those who survive gain skill, good leaders rise to the top, and units become more cohesive over time. Counterintuitively, as the Vietnam War progressed, the American frontline force weakened. In 1966, remembered Paul Gorman, the battalion he commanded had fourteen senior sergeants who had been in the unit for more than ten years, all of them trained by a legendary sergeant major who had landed at Normandy with the Big Red One. By contrast, he said, five years later, when he was commanding a brigade in the 101st Airborne, good sergeants who could provide the backbone of units, especially by maintaining standards and enforcing discipline, were hard to find. “I didn’t have the NCOs [non-commissioned officers]. The NCOs were gone.” By 1969, draftees made up 88 percent of the infantry riflemen in Vietnam. Another 10 percent was made up of first term volunteers, meaning that the fighting force was almost entirely inexperienced and often led by novice first term NCOs and officers. In one company in 1970, of two hundred men, only three—the captain, one platoon sergeant, and one squad leader—had been in the Army for more than two years. In addition, because of the rotation policy, units not only arrived green but stayed that way. “After only two months in Vietnam, I had more experience than half the men in Vietnam,” recalled one sergeant. There were plenty of career soldiers in Vietnam, but they disproportionately served at higher headquarters, not in line units doing the fighting.”