Washington ? There was a moment in “The Fog of War” when I thought this sober film on the life and times of Robert McNamara should be required viewing for those who believe that even a good war is free of moral dilemmas.

Remembering the firebombing of Tokyo, the death of 100,000 civilians in one night in World War II, McNamara asks: Would we have been tried as war criminals if we’d lost?

There was another moment when I thought the film should be viewed as well by those who believe that American vulnerability began on Sept. 11, 2001.

Remembering the Cuban missile crisis, the old Cold Warrior says: “At the end we lucked out. It was luck that prevented nuclear war.”

But by the time the film ran through the aging whiz kid’s schoolbook — “Eleven Lessons from the Life of Robert S. McNamara” — I was convinced that it should be seen most of all by those who are too young to remember when the Vietnam War was called McNamara’s War.

No, I am not someone who believes that Iraq is another Vietnam. Every war — if I may mangle Tolstoy — is unhappy in its own way. But you can’t hear McNamara alternately justifying and apologizing for his role as secretary of defense, running his tongue across the painful tooth of his involvement again and again, without hearing echoes.

“What makes us omniscient?” asks the man once described as an IBM machine with legs. “If we can’t persuade nations with comparable values of the merit of our cause, we better re-examine our reasons.”

Re-examine our reasons? In the mid-1960s, McNamara remembers, we escalated the war in Vietnam on wrong information, on mistaken and misinterpreted reports of torpedo attacks. In 2003, we launched a pre-emptive war on the grounds that Saddam Hussein had weapons of mass destruction at the ready. Wrong again.

Today the fog of this war is also lifting. In his exit interview, David Kay, the weapons inspector, talked openly to reporters about the errors of our prewar intelligence. As he led the failed search for weapons of mass destruction, Kay said, analysts came up to him “almost in tears … apologizing for reaching the conclusions that they did.” But no one, he laments, ever stood up and said let’s examine the basis for our conclusions.

President Bush remains anything but apologetic. In his State of the Union address, he switched the subject from weapons of mass destruction to “weapons of mass destruction-related program activities.” He’s switched the justification for this war and its casualties to the insistence that the world is better off without Saddam. He is trying to write the history our grandchildren will read.

McNamara and Bush, Vietnam and Iraq, sent me searching back to the words of my friend the late James Thomson, curator of the Nieman program when I was a young journalism fellow at Harvard. Jim was a golden boy, the son of missionaries to China, who left the government and then spoke out against the Vietnam War.

His powerful autopsy of the War — “How Could Vietnam Happen?” — was published in 1968 just weeks after McNamara’s resignation in disagreement with President Johnson. Vietnam, he wrote, was the result of wishful thinking, overselling, the neutralizing of dissent within government and the idea that the war was a fundamental test of national will.

He concluded: “To put it bluntly: At the heart of the Vietnam calamity is a group of able, dedicated men who have been regularly and repeatedly wrong — and whose standing with their contemporaries, and more important, with history, depends, as they see it, on being proven right. These are not men who can be asked to extricate themselves from error.”

Do I hear Iraq? When McNamara left the Pentagon and Thomson wrote this autopsy, we were only halfway through the Vietnam War. We were seven years and nearly 31,000 more deaths from the end. How will that chilling fact echo?

Through the primary season, Democrats have debated how we got into Iraq: Was it misinformation or disinformation? In the general election, it is likely to refocus on who can find an end without leaving a greater disaster in its wake.

I think of the question Thomson described in his 1968 piece. Once, Henry Stimson, secretary of war for Taft, FDR and Truman, was asked: How can we bring peace to the world?

Stimson answered: “You begin by bringing to Washington a small handful of able men who believe that the achievement of peace is possible. You work them to the bone until they no longer believe that it is possible. And then you throw them out — and bring in a new bunch who believe that it is possible.”

– Ellen Goodman is a columnist for Washington Post Writers Group.