民意對美國政治之影響---以1968年越戰之新春攻勢為例

The Impact of Public Opinion on American Politics-A Case Study of Tet Offensive,1968

趙五鼎(Wu-Ting Chao)

指導教授 ： 陳一新

淡江大學/國際研究學院/美國研究所碩士班/碩士(2008年)

https://doi.org/10.6846/TKU.2008.00081

摘要

越戰從1965年升高至1975年美軍撤出，所費10年。在這10年中，民意之表現有日漸激烈之趨勢，不僅舉辦多場示威遊行活動，更於1968年發生數起衝突事件。民意對越戰的不滿急速上升起因於新春攻勢 (Tet Offensive) 之爆發。1968年1月30日凌晨由北越所發動之新春攻勢成為越戰關鍵戰役之一。新春攻勢前美國政府對民眾信心喊話，表示越戰情況樂觀，美軍將邁向勝利。但是，新春攻勢的發生打破政府所掩蓋的真相。經由媒體的報導將當地駁火的畫面傳回國內，改變民眾對於越戰的觀感。新春攻勢後，美國國內對越戰的反彈升高。不僅民意的不滿逐漸高漲，媒體也大肆發表對越戰悲觀的評論，加上長年因為戰爭花費導致經濟損耗，以及南越情勢持續不穩。最終使得詹森總統於1968年3月31日在電視公開演說中發表將停火以求和談，並且不再競選總統連任之決定。
本論文針對民意對美國政治與外交政策三者之相互關係作為研究重點。除了對越戰背景以及新春攻勢前後之情勢做簡單陳述外，主要以蓋洛普 (George H. Gallup) 之民意調查來顯示1965至1968年民意之轉變。此外，本論文以民意為變數，用艾理遜 (Graham T. Allison) 教授決策模式之理性行為模式來檢視詹森於1968年3月31日所作之決定。希望可以藉由理論之檢驗，證明民意在決策過程中確實影響決策者。
本論文的主旨在於，雖然在冷戰的氛圍下，美國必須堅守其承諾並提防「骨牌理論」(Domino Theory) 對東南亞國家所引發的赤化效應；但是，在新春攻勢發生後，美國已無法繼續一場沒有勝算的戰爭，以致於詹森必須作出停火與和談的決定，以平息當前反戰的民意，並且還能繼續處理越南問題以維護美國在東南亞之利益。

關鍵字

新春攻勢 ； 民意 ； 理性行為者模式 ； 詹森

並列摘要

From the escalation of Vietnam War in 1965 to the withdrawal of Vietnam in 1975, the United States cost a whole decade. During this decade, public opposition to Vietnam War increased by degrees. There were not only lots of demonstrations but also quite a few violent conflicts in 1968. Tet offensive was the main reason of the changing public opinion. On January 30, 1968, North Vietnamese launched an attack by surprise and this became the crucial assault during the Vietnam War. Before this attack, the United States showed great confident in this war; however, Tet offensive presented to American people the truth behind official statement. Pictures of Tet offensive delivered by media also turned public opinion against the war. Besides the influence of the media and public opinion, the cost of the war made American economy decrease, and the continuing turmoil of South Vietnam forced Lyndon B. Johnson to change his Vietnam policy. On March 31, 1968, Johnson announced in the television speech that he would stop the bombing to seek the negotiation with North Vietnam, and that he would not seek for the nomination for the next presidential election.
This thesis focuses on the relationship between public opinion, U.S. politics and foreign policy. For this instance, the thesis not only discusses the basic background of Vietnam War and Tet offensive but also uses Gallup Poll to describe the shift of public opinion from 1965 to 1968. Moreover, the thesis takes public opinion as the variable, and uses rational actor model of Graham Allison’s decision-making theory to analyze LBJ’s decision on March 31, 1968.
The main theme of this thesis is that even in the Cold-War era, the United States had to commit the promise to his alliance, and to prevent the sovietization in South East Asia by Domino theory. Nevertheless, after Tet offensive, the United States could not continue the war without any advantage. Therefore, LBJ had to halt the bombing to seek negotiation so as to appease the public opinion. This decision enabled the United States to continue tackling the Vietnam problem and to protect the U.S. interests in South East Asia.

並列關鍵字

Tet offensive ； public opinion ； Rational Actor Model ； Lyndon B. Johnson

參考文獻

Foreign Relations of United States 1964-1968, Vol. VI, Vietnam. http://www.state.gov/r/pa/ho/frus/johnsonlb/vi/

II. Books

Allison, Graham T. and Philip Zelikow, Essence of Decision: Explaining the Cuban Missile Crisis, 2nd. New York: Longman, 1999.

Aronson, James, The Press and the Cold War. New York : The Bobbs Merrill Company, 1970.

Braestrup, Peter, Big Story: How the American Press and Television Reported and Interpreted the Crisis of Tet 1968 in Vietnam and Washington. New York: Anchor Books, 1978.