Vietnam War

==Vietnamization, 1969–1972==

===Nuclear threats and diplomacy===
U.S. president Richard Nixon began troop withdrawals in 1969. His plan to build up the ARVN so that it could take over the defense of South Vietnam became known as "[[Vietnamization]]". As the PAVN/VC recovered from their 1968 losses and generally avoided contact, Creighton Abrams conducted operations aimed at disrupting logistics, with better use of firepower and more cooperation with the ARVN.<ref name=Hastings/>{{Rp|517}} On 27 October 1969, Nixon had ordered a squadron of 18 B-52s loaded with nuclear weapons [[Operation Giant Lance|to race to the border of Soviet airspace]] to convince the Soviet Union, in accord with the [[madman theory]], that he was capable of anything to end the Vietnam War.<ref>{{Cite journal |last1=Sagan |first1=Scott Douglas |last2=Suri |first2=Jeremi |date=16 June 2003 |title=The Madman Nuclear Alert: Secrecy, Signaling, and Safety in October 1969 |url=https://muse.jhu.edu/article/43692 |journal=International Security |language=en |volume=27 |issue=4 |pages=150–183 |doi=10.1162/016228803321951126 |issn=1531-4804 |s2cid=57564244}}</ref><ref>{{Cite web |last=Evans |first=Michael |title=Nixon's Nuclear Ploy |url=https://nsarchive2.gwu.edu/NSAEBB/NSAEBB81/index2.htm |access-date=8 February 2018 |website=nsarchive2.gwu.edu|archiveurl=https://web.archive.org/web/20230407114836/https://nsarchive2.gwu.edu/NSAEBB/NSAEBB81/index2.htm|archive-date=April 7, 2023}}</ref> Nixon had also sought [[détente]] with the Soviet Union and [[Sino-American relations#Rapprochement|rapprochement with China]], which decreased global tensions and led to nuclear arms reduction by both superpowers; however, the Soviets continued to supply the North Vietnamese with aid.<ref>{{Cite web |title=Foundations of Foreign Policy, 1969-1972 |url=https://2001-2009.state.gov/r/pa/ho/frus/nixon/i/21100.htm |access-date=4 July 2021 |website=Foreign Relations, 1969-1976, Volume I |publisher=U.S. Department of State|archiveurl=https://web.archive.org/web/20230513100856/https://2001-2009.state.gov/r/pa/ho/frus/nixon/i/21100.htm|archive-date=May 13, 2023}}</ref><ref>{{Cite journal |last=Van Ness |first=Peter |date=December 1986 |title=Richard Nixon, the Vietnam War, and the American Accommodation with China: A Review Article |journal=Contemporary Southeast Asia |volume=8 |issue=3 |pages=231–245 |jstor=25797906}}</ref>

===Hanoi's war strategy===
[[File:Vietnampropaganda.png|thumb|upright|Propaganda leaflet urging the defection of [[Viet Cong]] and [[North Vietnam]]ese to the side of the [[Republic of Vietnam]]]]

In September 1969, Ho Chi Minh died at age 79.<ref>{{Cite news |date=4 September 1969 |title=Ho Chi Minh Dies of Heart Attack in Hanoi |page=1 |work=The Times}}</ref> The failure of the 1968 Tet Offensive in sparking a popular uprising in the south caused a shift in Hanoi's war strategy, and the [[Võ Nguyên Giáp|Giáp]]-[[Trường Chinh|Chinh]] "Northern-First" faction regained control over military affairs from the Lê Duẩn-[[Hoàng Văn Thái]] "Southern-First" faction.<ref name="Currey">{{Cite book |last=Currey |first=Cecil B. |title=Victory at Any Cost: The Genius of Viet Nam's Gen. Vo Nguyen Giap |date=2005 |publisher=Potomac Books, Inc. |isbn=978-1-57488-742-6 |page=[{{GBurl|id=jm-jh1_D0I4C|p=272}} 272]}}</ref>{{Rp|272–274}} An unconventional victory was sidelined in favor of a strategy built on conventional victory through conquest.<ref name=Nguyen/>{{Rp|196–205}} Large-scale offensives were rolled back in favor of [[Low intensity conflict|small-unit]] and [[Sapper#PAVN and Viet Cong|sapper]] attacks as well as targeting the pacification and Vietnamization strategy.<ref name=Currey/> In the two-year period following Tet, the PAVN had begun its transformation from a fine [[Light infantry|light-infantry]], limited mobility force into a [[Maneuver warfare|high-mobile]] and mechanized [[combined arms]] force.<ref name=Currey/>{{Rp|189}} By 1970, over 70% of communist troops in the south were northerners, and southern-dominated VC units no longer existed.<ref>{{Cite book |last=Kiernan |first=Ben |title=Viet Nam: A History from Earliest Times to the Present |date=February 2017 |publisher=Oxford University Press |page=447}}</ref>

===U.S. domestic controversies===
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 1968 [[My Lai Massacre]],<ref name=Hastings/>{{Rp|518–521}} in which a U.S. Army unit raped and killed civilians, and the 1969 "[[Green Beret Affair]]", where eight [[United States Army Special Forces|Special Forces]] soldiers, including the 5th Special Forces Group Commander, were arrested for the murder<ref>{{Cite book |last=Stein |first=Jeff |url=https://archive.org/details/murderinwartimeu00stei |title=A Murder in Wartime: The Untold Spy Story that Changed the Course of the Vietnam War |date=1992 |publisher=St. Martin's Press |isbn=978-0-312-07037-3 |pages=[https://archive.org/details/murderinwartimeu00stei/page/60 60–2] |url-access=registration}}</ref> of a suspected double agent,<ref>{{Cite web |last=Bob Seals |date=2007 |title=The "Green Beret Affair": A Brief Introduction |url=http://www.militaryhistoryonline.com/20thCentury/articles/greenberets.aspx|archiveurl=https://web.archive.org/web/20080509150017/http://www.militaryhistoryonline.com/20thCentury/articles/greenberets.aspx|archive-date=May 9, 2008}}</ref> provoked national and international outrage.

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 [[United States Department of Defense|Department of Defense]], detailed a long series of public deceptions on the part of the U.S. government. The [[Supreme Court of the United States|Supreme Court]] ruled that its publication was legal.<ref>{{Cite journal |last=[[USA.gov]] |date=February 1997 |title=The Pentagon Papers Case |url=http://usinfo.state.gov/journals/itdhr/0297/ijde/goodsb1.htm |url-status=dead |journal=eJournal USA |volume=2 |issue=1 |archive-url=https://web.archive.org/web/20080112095748/http://usinfo.state.gov/journals/itdhr/0297/ijde/goodsb1.htm |archive-date=12 January 2008 |access-date=27 April 2010}}</ref>

===Collapsing U.S. morale===
{{Further|G.I. movement}}
Following the Tet Offensive and the decreasing support among the U.S. public for the war, U.S. forces began a period of morale collapse, disillusionment and disobedience.<ref name="Stewart">{{Cite book |last=Stewart |first=Richard |url=https://history.army.mil/books/AMH-V2/AMH%20V2/chapter11.htm |title=American Military History, Volume II, The United States Army in a Global Era, 1917–2003 |date=2005 |publisher=[[United States Army Center of Military History]] |isbn=978-0-16-072541-8}}</ref>{{Rp|349–350}}<ref name="Daddis">{{Cite book |last=Daddis |first=Gregory A. |title=Withdrawal: Reassessing America's Final Years in Vietnam |date=2017 |publisher=Oxford University Press |isbn=978-0-19-069110-3 |page=[{{GBurl|id=a3QzDwAAQBAJ|pg=PT172}} 172]}}</ref>{{Rp|166–175}} At home, desertion rates quadrupled from 1966 levels.<ref name="Heinl">{{Cite journal |last=Heinl |first=Robert D. Jr. |date=7 June 1971 |title=The Collapse of the Armed Forces |url=https://msuweb.montclair.edu/~furrg/Vietnam/heinl.pdf |journal=Armed Forces Journal}}</ref> Among the enlisted, only 2.5% chose infantry combat positions in 1969–1970.<ref name=Heinl/> [[Reserve Officers' Training Corps|ROTC]] enrollment decreased from 191,749 in 1966 to 72,459 by 1971,<ref>{{Cite book |last=Sevy |first=Grace |title=The American Experience in Vietnam: A Reader |date=1991 |publisher=University of Oklahoma Press |isbn=978-0-8061-2390-5 |page=[{{GBurl|id=dZg3emyCL6EC|p=172}} 172]}}</ref> and reached an all-time low of 33,220 in 1974,<ref>{{Cite news |last=Richard Halloran |date=12 August 1984 |title=R.O.T.C. Booming as Memories of Vietnam Fade |work=The New York Times |url=https://www.nytimes.com/1984/08/12/us/rotc-booming-as-memories-of-vietnam-fade.html |access-date=14 June 2018|archiveurl=https://web.archive.org/web/20230415124225/https://www.nytimes.com/1984/08/12/us/rotc-booming-as-memories-of-vietnam-fade.html|archive-date=April 15, 2023}}</ref> depriving U.S. forces of much-needed military leadership.

Open refusal to engage in patrols or carry out orders and disobedience began to emerge during this period, with one notable case of an entire company refusing orders to engage or carry out operations.<ref>{{Cite news |date=23 March 1971 |title=General Won't Punish G.I.'s for Refusing Orders |work=The New York Times |url=https://www.nytimes.com/1971/03/23/archives/general-wont-punish-gis-for-refusing-orders-53-defiant-gis-escape.html |access-date=13 June 2018|archiveurl=https://web.archive.org/web/20230409031624/https://www.nytimes.com/1971/03/23/archives/general-wont-punish-gis-for-refusing-orders-53-defiant-gis-escape.html|archive-date=April 9, 2023}}</ref> Unit cohesion began to dissipate and focused on minimizing contact with Viet Cong and PAVN.<ref name=Daddis/>{{Rp|}} A practice known as "sand-bagging" started occurring, where 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.<ref name=Ward/>{{Rp|407–411}} Drug usage increased rapidly among U.S. forces during this period, as 30% of U.S. troops regularly used marijuana,<ref name=Ward/>{{Rp|407}} while a House subcommittee found 10–15% of U.S. troops in Vietnam regularly used high-grade heroin.<ref name=Heinl/><ref name=Hastings/>{{Rp|526}} From 1969 on, search-and-destroy operations became referred to as "search and evade" or "search and avoid" operations, falsifying battle reports while avoiding guerrilla fighters.<ref>{{Cite journal |last=Robert |first=Graham |date=1984 |title=Vietnam: An Infantryman's View of Our Failure |url=https://web.viu.ca/davies/H323Vietnam/Vietnam.InfantryView.failure.pdf |journal=Military Affairs |volume=48 |issue=3 (Jul. 1984) |pages=133–139 |doi=10.2307/1987487 |jstor=1987487|archiveurl=https://web.archive.org/web/20230605173405/https://web.viu.ca/davies/H323Vietnam/Vietnam.InfantryView.failure.pdf|archive-date=June 5, 2023}}</ref> A total of 900 fragging and suspected [[fragging]] incidents were investigated, most occurring between 1969 and 1971.<ref name="Stanton">{{Cite book |last=Stanton |first=Shelby L. |title=The Rise and Fall of an American Army: U.S. Ground Forces in Vietnam, 1963–1973 |date=2007 |publisher=Random House Publishing Group |isbn=978-0-307-41734-3}}</ref>{{Rp|331}}<ref name=Ward/>{{Rp|407}} In 1969, field-performance of the U.S. Forces was characterized by lowered morale, lack of motivation, and poor leadership.<ref name=Stanton/>{{Rp|331}} The significant decline in U.S. morale was demonstrated by the [[Battle of FSB Mary Ann]] in March 1971, in which a sapper attack inflicted serious losses on the U.S. defenders.<ref name=Stanton/>{{Rp|357}} William Westmoreland, no longer in command but tasked with investigation of the failure, cited a clear dereliction of duty, lax defensive postures and lack of officers in charge as its cause.<ref name=Stanton/>{{Rp|357}}

On the collapse of U.S. morale, historian Shelby Stanton wrote:

{{Blockquote|In the last years of the Army's retreat, its remaining forces were relegated to static security. The American Army's decline was readily apparent in this final stage. Racial incidents, drug abuse, combat disobedience, and crime reflected growing idleness, resentment, and frustration{{Nbsp}}... the fatal handicaps of faulty campaign strategy, incomplete wartime preparation, and the tardy, superficial attempts at Vietnamization. An entire American army was sacrificed on the battlefield of Vietnam.<ref name=Stanton/>{{Rp|366–368}}}}

===ARVN taking the lead and U.S. ground-force withdrawal===
[[File:ARVN and US Special Forces.jpg|thumb|ARVN and US Special Forces, September 1968]]

Beginning in 1970, American troops were withdrawn from border areas where most of the fighting took place and instead redeployed along the coast and interior. US casualties in 1970 were less than half of 1969 casualties after being relegated to less active combat.<ref name="upi1970">{{Cite web |title=Vietnamization: 1970 Year in Review |url=http://www.upi.com/Audio/Year_in_Review/Events-of-1970/Apollo-13/12303235577467-2/#title |archive-url=https://web.archive.org/web/20110831125343/http://www.upi.com/Audio/Year_in_Review/Events-of-1970/Apollo-13/12303235577467-2 |archive-date=31 August 2011 |website=UPI.com}}</ref> While U.S. forces were redeployed, the ARVN took over combat operations throughout the country, with casualties double US casualties in 1969, and more than triple US ones in 1970.<ref name="Wiest">{{Cite book |last=Wiest |first=Andrew |title=Vietnam's Forgotten Army: Heroism and Betrayal in the ARVN |date=2007 |publisher=NYU Press |isbn=978-0-8147-9451-7 |pages=[{{GBurl|id=r3dez4JhXUQC|p=124}} 124]–140}}</ref> In the post-Tet environment, membership in the [[South Vietnamese Regional Force]] and [[South Vietnamese Popular Force|Popular Force]] militias grew, and they were now more capable of providing village security, which the Americans had not accomplished under Westmoreland.<ref name=Wiest/>

In 1970, Nixon announced the withdrawal of an additional 150,000 American troops, reducing the number of Americans to 265,500.<ref name=upi1970/> By 1970, Viet Cong forces were no longer southern-majority, as nearly 70% of units were northerners.<ref>{{Cite book |last=Porter |first=Gareth |title=Vietnam: The Politics of Bureaucratic Socialism |date=1993 |isbn=978-0-8014-2168-6 |page=26|publisher=Cornell University Press }}</ref> Between 1969 and 1971 the Viet Cong and some PAVN units had reverted to [[small unit tactics]] typical of 1967 and prior instead of nationwide grand offensives.<ref name=Nguyen/>{{Rp|}} In 1971, Australia and New Zealand withdrew their soldiers and U.S. troop count was further reduced to 196,700, with a deadline to remove another 45,000 troops by February 1972. The United States also reduced support troops, and in March 1971 the [[5th Special Forces Group (United States)|5th Special Forces Group]], the first American unit deployed to South Vietnam, withdrew to [[Fort Bragg]], [[North Carolina]].<ref name="StantonVOB">{{Cite book |last=Stanton |first=Shelby L. |title=Vietnam order of battle |date=2003 |publisher=Stackpole Books |isbn=978-0-8117-0071-9}}</ref>{{Rp|240}}{{Refn|On 8 March 1965 the first American combat troops, the [[3rd Marine Division (United States)#Vietnam War|Third Marine Regiment, Third Marine Division]], began landing in Vietnam to protect the [[Da Nang Air Base]].{{Sfn|Willbanks|2009|p=110}}<ref>{{Cite web |date=2010 |title=Facts about the Vietnam Veterans memorial collection |url=http://www.nps.gov/mrc/reader/vvmcr.htm |url-status=dead |archive-url=https://web.archive.org/web/20100528032742/http://www.nps.gov/mrc/reader/vvmcr.htm |archive-date=28 May 2010 |access-date=26 April 2010 |publisher=[[National Park Service]]}}</ref>|group="A"}}

===Cambodia===
{{Main|Operation Menu|Operation Freedom Deal|5=Cambodian Civil War}}
[[File:Vietconginterrogation.jpg|thumb|upright|An alleged Viet Cong captured during an attack on an American outpost near the Cambodian border is interrogated.]]

Prince [[Norodom Sihanouk]] had proclaimed Cambodia neutral since 1955,<ref>{{Cite journal |last=Sihanouk |first=Prince Norodom |title=Cambodia Neutral: The Dictates of Necessity |journal=Foreign Affairs |volume=1958 |pages=582–583}}</ref> but permitted the PAVN/Viet Cong to use the port of [[Sihanoukville Autonomous Port|Sihanoukville]] and the [[Sihanouk Trail]]. In March 1969 Nixon launched a massive secret bombing campaign, called [[Operation Menu]], against communist sanctuaries along the Cambodia/Vietnam border. Only five high-ranking congressional officials were informed of Operation Menu.{{Refn|group="A"|They were: Senators [[John C. Stennis]] (MS) and [[Richard B. Russell]] Jr. (GA) and Representatives [[Lucius Mendel Rivers]] (SC), [[Gerald R. Ford]] (MI) and [[Leslie C. Arends]] (IL). Arends and Ford were leaders of the Republican minority and the other three were Democrats on either the Armed Services or Appropriations committees.}}

In March 1970, Prince [[Cambodian coup of 1970|Sihanouk was deposed]] by his [[pro-American]] prime minister [[Lon Nol]], who demanded that North Vietnamese troops leave Cambodia or face military action.<ref>{{Cite book |last=Sutsakhan |first=S. |url=https://www.vietnam.ttu.edu/star/images/239/2390505001A.pdf |title=The Khmer Republic at War and the Final Collapse |date=1987 |publisher=United States Army Center of Military History |page=42 |archive-url=https://web.archive.org/web/20190412060055/https://www.vietnam.ttu.edu/star/images/239/2390505001A.pdf |archive-date=12 April 2019 |url-status=dead}}</ref> Lon Nol began rounding up Vietnamese civilians in Cambodia into internment camps and massacring them, provoking harsh reactions from both the North Vietnamese and South Vietnamese governments.<ref>{{Cite book |last1=Lipsman |first1=Samuel |url=https://archive.org/details/fightingfortime00lips/page/145 |title=The Vietnam Experience Fighting for time |last2=Doyle |first2=Edward |date=1983 |publisher=Boston Publishing Company |isbn=978-0-939526-07-9 |page=[https://archive.org/details/fightingfortime00lips/page/145 145]}}</ref> In April–May 1970, North Vietnam invaded Cambodia at the request of the [[Khmer Rouge]] following negotiations with deputy leader [[Nuon Chea]]. Nguyen Co Thach recalls: "Nuon Chea has asked for help and we have liberated five provinces of Cambodia in ten days."<ref>{{Cite book |last=Susan E. Cook |url=https://gsp.yale.edu/genocide-cambodia-and-rwanda-0 |title=Genocide in Cambodia and Rwanda |date=2004 |publisher=Yale University |series=Yale Genocide Studies Program Monograph Series |page=54|archiveurl=https://web.archive.org/web/20230409052610/https://gsp.yale.edu/genocide-cambodia-and-rwanda-0|archive-date=April 9, 2023}}</ref> U.S. and ARVN forces launched the [[Cambodian Campaign]] in May to attack PAVN and Viet Cong bases. A counter-offensive in 1971 as part of [[Operation Chenla II]] by the PAVN would recapture most of the border areas and decimate most of Lon Nol's forces.

The U.S. incursion into Cambodia sparked [[Protests against the Vietnam War|nationwide U.S. protests]] as Nixon had promised to deescalate the American involvement. [[Kent State shootings|Four students were killed by National Guardsmen]] in May 1970 during a protest at [[Kent State University]] in [[Ohio]], which provoked further public outrage in the United States. The reaction to the incident by the Nixon administration was seen as callous and indifferent, reinvigorating the declining anti-war movement.<ref name=Daddis/>{{Rp|128–129}} The U.S. Air Force continued to heavily bomb Cambodia in support of the Cambodian government as part of [[Operation Freedom Deal]].

===Laos===
{{Main|3=Operation Commando Hunt|4=Laotian Civil War|6=Operation Lam Son 719}}

Building up on the success of ARVN units in Cambodia, and further testing the Vietnamization program, the ARVN were tasked to launch [[Operation Lam Son 719]] in February 1971, the first major ground operation aimed directly at attacking the Ho Chi Minh trail by attacking the major crossroad of Tchepone. This offensive would also be the first time the PAVN would field-test its combined arms force.<ref name=Nguyen/>{{Rp|}} The first few days were considered a success but the momentum had slowed after fierce resistance. Thiệu had halted the general advance, leaving armored divisions able to surround them.{{Sfn|Willbanks|2014|p=89}}

Thieu had ordered [[air assault]] troops to capture Tchepone and withdraw, despite facing four-times larger numbers. During the withdrawal the PAVN counterattack had forced a panicked rout. Half of the ARVN troops involved were either captured or killed, half of the ARVN/US support helicopters were downed by anti-aircraft fire and the operation was considered a fiasco, demonstrating operational deficiencies still present within the ARVN.<ref name=Karnow/>{{Rp|644–645}} Nixon and Thieu had sought to use this event to show-case victory simply by capturing Tchepone, and it was spun off as an "operational success".{{Sfn|Willbanks|2014|p=118}}<ref name=Hastings/>{{Rp|576–582}}

===Easter Offensive and Paris Peace Accords, 1972===
[[File:СВС у обломков сбитого Б-52 в окрестностях Ханоя 23.12.1972 (1).jpg|thumb|Soviet advisers inspecting the debris of a B-52 downed in the vicinity of Hanoi]]

Vietnamization was again tested by the [[Easter Offensive]] of 1972, a massive conventional PAVN invasion of South Vietnam. The PAVN quickly overran the northern provinces and in coordination with other forces attacked from Cambodia, threatening to cut the country in half. U.S. troop withdrawals continued, but American airpower responded, beginning [[Operation Linebacker]], and the offensive was halted.<ref name=Hastings/>{{Rp|606–637}}

The war was central to the [[1972 United States presidential election|1972 U.S. presidential election]] as Nixon's opponent, [[George McGovern]], campaigned on immediate withdrawal. Nixon's National Security Advisor, [[Henry Kissinger]], had continued secret negotiations with North Vietnam's [[Lê Đức Thọ]] and in October 1972 reached an agreement. President Thieu demanded changes to the peace accord upon its discovery, and when North Vietnam went public with the agreement's details, the Nixon administration claimed they were attempting to embarrass the president. The negotiations became deadlocked when Hanoi demanded new changes. To show his support for South Vietnam and force Hanoi back to the negotiating table, Nixon ordered [[Operation Linebacker II]], a massive bombing of Hanoi and Haiphong 18–29 December 1972.<ref name=Hastings/>{{Rp|649–663}} Nixon pressured Thieu to accept the terms of the agreement or else face retaliatory military action from the U.S.<ref>{{Cite book |last=Beschloss |first=Michael |title=Presidents of War: The Epic Story, from 1807 to Modern Times |date=2018 |publisher=Crown |isbn=978-0-307-40960-7 |location=New York |page=579}}</ref>

On 15 January 1973, all U.S. combat activities were suspended. Lê Đức Thọ and Henry Kissinger, along with the PRG Foreign Minister [[Nguyễn Thị Bình]] and a reluctant President Thiệu, signed the Paris Peace Accords on 27 January 1973.<ref name=Ward/>{{Rp|508–513}} This officially ended direct U.S. involvement in the Vietnam War, created a ceasefire between North Vietnam/PRG and South Vietnam, guaranteed the territorial integrity of Vietnam under the Geneva Conference of 1954, called for elections or a political settlement between the PRG and South Vietnam, allowed 200,000 communist troops to remain in the south, and agreed to a POW exchange. There was a sixty-day period for the total withdrawal of U.S. forces. "This article", noted Peter Church, "proved{{Nbsp}}... to be the only one of the Paris Agreements which was fully carried out."<ref>{{Cite book |last=Church |first=Peter |title=A Short History of South-East Asia |date=2006 |publisher=John Wiley & Sons |isbn=978-0-470-82181-7 |pages=193–194}}</ref> All U.S. forces personnel were completely withdrawn by March 1973.<ref name=Herring/>{{Rp|260}}