(CNN)  -- On June 17, 1964, President Lyndon Johnson explained to The New York Times reporter James "Scotty" Reston why he had to stay the course in Vietnam by stabilizing the South Vietnamese government so that it could fight communism. Johnson rejected calls for withdrawal that were being made by liberal Democrats as well as the proposal for neutralization promoted by France's Charles de Gaulle. "So the only thing you've got left," Johnson said, "is try to make this thing more efficient and more effective and hold as strong as you can and keep this government as stable as you can and try to improve it as you can and that we're doing day and night."
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Zelizer: Some Vietnam-Afghanistan comparisons have merit
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It is impossible to ignore the challenges Obama faces in Afghanistan, he says
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Zelizer: Obama should use lessons of Vietnam as a guide
Afghanistan
Afghanistan
Most of those who have compared @placeholder to Vietnam do not say that the situations were exactly the same politically or strategically.
Afghanistan
Afghanistan
Nor is it inevitable that the surge in @placeholder will be unsuccessful.
Lyndon Johnson
Johnson
Johnson
Despite the fact that @placeholder confronted a very different kind of enemy, the risk today is enormously high.
Lyndon Johnson
Johnson
Johnson
Rather, he should use @placeholder's experience to help guide him as he makes crucial decisions in the months ahead and attempts to navigate the challenges of the wartime presidency.
Lyndon Johnson
Johnson
Johnson
In a conversation with a few of his closest advisers, @placeholder said in 1964 that "It's damned easy to get in a war but it's gonna be awfully hard to ever extricate yourself if you get in."
Obama
Obama
Let's hope that this time around @placeholder does not repeat this error.