<P> The anti-war movement was gaining strength in the United States . Nixon appealed to the "silent majority" of Americans who he said supported the war without showing it in public . But revelations of the My Lai Massacre, in which a U.S. Army platoon raped and killed civilians, and the 1969 "Green Beret Affair" where eight Special Forces soldiers, including the 5th Special Forces Group Commander, were arrested for the murder of a suspected double agent provoked national and international outrage . </P> <P> In 1971 the Pentagon Papers were leaked to The New York Times . The top - secret history of U.S. involvement in Vietnam, commissioned by the Department of Defense, detailed a long series of public deceptions on the part of the U.S. government . The Supreme Court ruled that its publication was legal . </P> <P> Following the Tet Offensive and the U.S. public beginning to publicly turn against the war, U.S. forces begun a period of morale collapse, disillusionment and disobedience . At home, desertion rates quadrupled from 1966 levels . Among enlisted only 2.5% chose infantry combat positions in 1969 - 1970 . ROTC enrollment decreased from 191,749 in 1966 to 72,459 by 1971 and reaching an all - time low of 33,220 in 1974, depriving U.S. forces of much - needed military leadership . </P> <P> Open refusal of engaging in patrols, carrying out orders and disobedience begun to emerge during this period as well with notable case of an entire company refusing orders to engage or carry out operations . Unit cohesion begun to dissipate, and focused on minimising contact with Viet Cong and NVA troops . A practice known as "sand - bagging" started occurring, were units ordered to go on patrol would go into the country - side, find a site out of view from superiors and rest while radioing in false coordinates and unit reports . Drug usage increased rapidly among U.S. forces during this period, as 30% of U.S. troops engaged in regular usage of marijuana while a House subcommittee found 10 - 15% of U.S. troops in Vietnam regularly used high - grade heroin . From 1969 on - ward search - and - destroy operations started to become referred to as "search and evade" or "search and avoid" operations, falsifying battle reports while avoiding guerrilla fighters . A total of 900 fragging and suspected fragging incidents were investigated, most occurring between 1969 and 1971 . In 1969 field - performance of the U.S. Forces was characterised by lowered morale, lack of motivation, and poor leadership . One battle which is used by historians to high - light the significant decline in U.S. morale was the Battle of FSB Mary Ann, one of the final engagements in which a sapper attack had rampaged and destroyed the base, relatively unchallenged . William Westmoreland, no - longer in command but tasked with its investigation cited a clear dereliction of duty, lax defensive postures and lack of officers being in charged as the reason . </P>

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