Bill Moyers, who was at the side of President Lyndon Johnson at the time when disastrous decisions were being made to escalate the U.S. presence in the quagmire that was Vietnam, used his experience to speak last Friday night to President Barack Obama about what could be an equally disastrous decision to escalate the U.S. presence in the quagmire that is Afghanistan.

“Our country wonders this weekend what is on President Obama’s mind,” Moyers began, at the opening of a remarkable hour of television. “He is apparently, about to bring months of deliberation to a close and answer General Stanley McChrystal’s request for more troops in Afghanistan. When he finally announces how many, why, and at what cost, he will most likely have defined his presidency, for the consequences will be far-reaching and unpredictable. As I read and listen and wait with all of you for answers, I have been thinking about the mind of another president, Lyndon B. Johnson.”

The presidential adviser turned journalist, who will retire his “Bill Moyers Journal” television program in April, then turned to decades old tapes that were recorded as Johnson was making the decision to surge hundreds of thousands of additional soldiers into a war that would kill almost 60,000 Americans and more than a million Vietnamese.

One point of the program, he explained, was to offer viewers “an insight into the mind of one president facing the choice of whether or not to send more and more American soldiers to fight in a far-away and strange place.”

But another point was to offer Obama and his aides, who seem to be determined to surge more troops into Afghanistan, a caution that only a few wise and worldly senators provided Johnson back in the mid-1960s — chief among them Oregon’s Wayne Morse, about whom Johnson says on one of the tapes: “outside Morse, everybody I talk to says you got to go in…”

Moyers was not making crude or casual analogies.

“Granted,” he explained early on, “Barack Obama is not Lyndon Johnson, Afghanistan is not Vietnam and this is now, not then. But listen and you will hear echoes and refrains that resonate today.”

The tapes of Johnson were indeed eerie and resonant, especially those where the former president says of the battle to which he is about to commit what he calls “the flower of our youth, our finest young men”: “I don’t think it’s worth fighting for and I don’t think we can get out. And it’s just the biggest damned mess that I ever saw.”

But even more powerful was the recognition that the man playing them was a witness to history who had learned from his experiences. For Moyers, there was something deeply personal and yet profoundly public about the statement he was making; before it aired Friday, he told me he saw the program as “one of the most important I’ve done in years.”

So it was.

And the most powerful part of a remarkably powerful program came at its conclusion, when Bill Moyers looked into the camera and said:

Now in a different world, at a different time, and with a different president, we face the prospect of enlarging a different war. But once again we’re fighting in remote provinces against an enemy who can bleed us slowly and wait us out, because he will still be there when we are gone.

Once again, we are caught between warring factions in a country where other foreign powers fail before us. Once again, every setback brings a call for more troops, although no one can say how long they will be there or what it means to win. Once again, the government we are trying to help is hopelessly corrupt and incompetent.

And once again, a President pushing for critical change at home is being pressured to stop dithering, be tough, show he’s got the guts, by sending young people seven thousand miles from home to fight and die, while their own country is coming apart.

And once again, the loudest case for enlarging the war is being made by those who will not have to fight it, who will be safely in their beds while the war grinds on. And once again, a small circle of advisers debates the course of action, but one man will make the decision.

We will never know what would have happened if Lyndon Johnson had said no to more war. We know what happened because he said yes.

It is possible to go to the “Bill Moyers Journal” website and view “A Tale of Quagmires.”

It is possible, as well, to visit the same site and read the transcript of a wise and nuanced rumination that is arguably the best statement available on both the war in Vietnam and the war in Afghanistan.