The Gulf of Tonkin and Americanization of the War

In this module, students will examine how and why the United States shifted from advisers to leaders in the Vietnam conflict. Students will view clips describing advisory roles, conduct a close read of the Gulf of Tonkin Resolution, and analyze political cartoons from the era.


The Gulf of Tonkin Resolution and the Americanization of the War in Vietnam

Essential Question

How did the Gulf of Tonkin resolution “Americanize” the war in Vietnam?


  • 5.D.1.e. Objective: Examine the causes and escalation of United States involvement in the Vietnam War, including the domino theory and the Tonkin Gulf resolution.
  • CCSS.ELA-LITERACY.RH.9-10.1 : Cite specific textual evidence to support analysis of primary and secondary sources, attending to such features as the date and origin of the information. (Grades 9/10)
  • CCSS.ELA-LITERACY.RH.11-12.7 : Integrate and evaluate multiple sources of information presented in diverse formats and media (e.g., visually, quantitatively, as well as in words) in order to address a question or solve a problem. (Grades 11/12)
  • CCSS.ELA-LITERACY.RH.11-12.8 : Evaluate an author's premises, claims, and evidence by corroborating or challenging them with other information. (Grades 11/12)
  • D2.His.1.9-12: Evaluate how historical events and developments were shaped by the unique circumstances of the time and place, as well as by broader historical contexts.
  • D2.His.4.9-12: Analyze complex and interacting factors that influenced the perspective of people during different historical eras.
  • 8.1 The United States responded to an uncertain and unstable post-war world by asserting and working to maintain a position of global leadership, with far-reaching domestic and international consequences.
    1. United States policymakers engaged in the Cold War with the authoritarian Soviet Union, seeking to limit the growth of communist military power and ideological influence, create a free-market global economy, and build an international security system.
      1. Post-war decolonization and the emergence of a powerful nationalist movement in Asia, Africa, and the Middle East led both sides in the Cold War to seek allies among new nations, many of which remained nonaligned.
    2. Cold War policies led to public debates over the power of the federal government and acceptable means of pursuing international and domestic goals while protecting civil liberties.
      1. Americans debated policies and methods designed to expose suspected communists within the United States even as both parties supported the broader strategy of containing communism.

Tips for using this module in your classroom


Documentary Clip

As students watch the film clip, have them answer the following questions:

  • American troops began an “advisory” role in Vietnam beginning in 1954. Describe some of the ways in which the American troops supported the South Vietnamese army.
  • What happened to the USS Maddox in the summer of 1964?
  • What was America’s immediate response to the attack?

Interview transcripts: Tom Glenn, Sal Formica, Bao Tran, Xuan Pham, Alan Phillips, Clark Mayer, David Hugel, Wayne McNeir, Bobbi Hovis, Mike Welch

Close Reading Primary Source Analysis

Analyze the Gulf of Tonkin Resolution and ask students:
  • What reasons does Congress provide to grant President Johnson additional military power? Cite three specific passages from the text.
  • Why is the Gulf of Tonkin Resolution sometimes referred to as a “blank check” for escalation? Find a passage which supports this assertion.
Examine the Senate vote on the Gulf of Tonkin Resolution .
Examine Herblock's "Domino Theory" political cartoon .
  • What is the message of the political cartoon?
  • What reasons does the author cite for U.S. involvement in Southeast Asia? Cite specific textual evidence.
  • Do these reasons support or refute the contentions made in the Gulf of Tonkin Resolution?
  • Does the author support increased involvement in Vietnam?