BOSTON — It was early August in the eighth year of America’s longest war and soldiers of two U.S. Army units were packing up and getting ready to come home.

That might sound like Afghanistan but the year was actually 1971. The war was in South Vietnam and the units were the 1st Brigade of the 5th Infantry Division and the 173rd Airborne Brigade. By December 31st of that year, U.S. military personnel in Vietnam would decline to 156,800, down from a peak of 543,400 reached in April 1969.

Sometimes it helps to look back so we can get a clearer picture of how to move ahead, and America desperately needs to take a hard look at the truth about the war in Afghanistan.

This is all the more important as we grieve the loss of 30 American Seal team members, their civilian interpreter and 7 Afghan commandos, all killed when their helicopter was shot down by the Taliban early last Saturday morning. It was the greatest single loss of U.S. forces since this tragic war began on October 7, 2001.

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While most of this country seems fixated on America’s economic woes, the debt crisis, the downgrade of the United States government credit rating, and a falling stock market, the War in Afghanistan grinds on toward its tenth anniversary.

Afghanistan is now indisputably America’s longest war and also its most invisible. Yet the brave sacrifice of America’s soldiers, Marines and other military personnel — and of their families — receives negligible coverage at best by the U.S. news media and the war is little discussed by the general public.

It’s an outrage — but there is virtually no outrage to be found on these shores.

So let’s state the unpleasant truth. This is a war we are not going to win. It’s also a war we can no longer afford to fight. America is out of money and out of options.

President Obama put America’s best general, David Petraeus, in charge of the war and Petraeus could not turn it around. The reality of the Taliban’s resilience is all too evident as is the ineptitude of the Afghan Army.

America went to war in Afghanistan with just cause: Osama bin Laden was using the country as his base of operations for Al Qaeda; from there he plotted the devastating attacks of September 11, 2001. America’s response came less than one month later when U.S. special forces and CIA agents quickly ousted the Taliban regime from Kabul and sent bin Laden and his henchmen scurrying for safety across the border in Pakistan.

Thankfully, bin Laden is now dead at the hands of members of the same Navy Seal team that suffered those devastating losses this weekend.

The Afghan War had a noble beginning. But as we approach the start of the war’s eleventh year, the only nobility left is the bravery of the young men and women still fighting on Afghanistan’s ancient battlefields. America has lost 1,727 troops killed and 11,191 wounded, many of them grievously. Last year was the most costly so far with 499 U.S. military deaths – and we could well exceed that number of fatalities in 2011.

There have been many comparisons between the War in Afghanistan and the Vietnam War but few, if any, are relevant other than the long, painful duration of each and the near certainty of a similar outcome: United States withdrawal without a clear victory.

It’s worth remembering how much Americans suffered in Vietnam, suffered and died for a losing cause.

The United States lost 58,272 killed, 303,644 wounded, and 1,687 missing in action. More than two and one half million Americans — volunteers and draftees — served their country in Vietnam, some as early as 1959 although combat units weren’t deployed until early 1965.

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There are varying interpretations of when the Vietnam War officially began but the Veterans Administration uses August 5, 1964, the date Congress passed the Tonkin Gulf Resolution which empowered the administration of President Lyndon Johnson to prosecute the war. There is no dispute about when full U.S. participation in the war came to an end. It was August 15, 1973.

And yet the war dragged on for almost two more years until the Viet Cong and the North Vietnamese Army roared into Saigon on April 30, 1975.

The last American troops to die in Vietnam were killed defending the U.S. Embassy on April 29, 1975 as evacuations of U.S. personnel were underway from the embassy roof. They were Marine Corporal Charles McMahon and Lance Corporal Darwin Judge.

Forty years ago a young John Kerry, then a leader of Vietnam Veterans against the War, testified before the Senate Foreign Relations Committee and posed his famous question: “How do you ask a man to be the last man to die for a mistake?”

That question resonates powerfully over the decades. Today America is in another long war in a very distant place facing a determined enemy fighting on its own soil. In a great irony of history John Kerry is now Chairman of the same Senate Foreign Relations Committee. He is also a close adviser to President Barack Obama and a supporter of the War in Afghanistan.

The Afghan War was not a mistake. But staying in it for ten years was.

President Obama, Senator Kerry and other leaders in Washington need to face the truth and accelerate the departure of U.S. troops.

It is inevitable that someone will have to be the last man, or woman, to die in Afghanistan. But it should not be inevitable that the war be blindly continued for one day longer than absolutely necessary.

Philip Balboni is Chief Executive Officer and Co-Founder of GlobalPost and served in Vietnam as an officer in the United States Army in 1965 and 1966.

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