Washington ? When Gordon Goldstein sees Afghanistan as “déjá vu,” a mission that’s “unraveling,” it isn’t the ramblings of another armchair critic.

Goldstein is the author of an acclaimed biography of McGeorge Bundy, the national security adviser under Presidents John F. Kennedy and Lyndon B. Johnson who became haunted by the misadventure he helped devise in Vietnam. The book, “Lessons in Disaster: McGeorge Bundy and the Path to War in Vietnam,” was on President Barack Obama’s nightstand as he was setting Afghanistan policy last year; it got a rave review from Richard Holbrooke, now in charge of the Afghanistan-Pakistan policy.

Goldstein argues it’s clear the counterinsurgency and population-protection policy, as set out in General Stanley McChrystal’s manifesto last summer, is failing, reminiscent of the grandiose plans Bundy promulgated in Vietnam in the 1960s.

There is emerging a consensus that the policy is heading south. This consensus includes the more than 100 House Democrats who voted against war funding last month, the chairman of the Republican National Committee, a growing number of foreign-policy elites outside the Obama administration, and the president of Pakistan.

Supposed differences, such as those displayed by Defense Secretary Robert Gates and House Speaker Nancy Pelosi in ABC News interviews last weekend over how substantial will be the troop withdrawals starting next summer, reflect a false choice. Given the situation and cost in lives and treasure, there seems little doubt Obama will scale back the U.S. commitment.

The other false debate grew out of the papers published on the Wikileaks website showing that elements of the Pakistani intelligence agency are cooperating with the Taliban; that is neither surprising nor unexpected.

The numbers underscore why this policy is unsustainable. U.S. casualties this year are likely to double to between 600 and 700, more than during the entire Bush administration; July was the deadliest month for U.S. forces in the history of the conflict.

The Afghan war will cost $105 billion this fiscal year, more than double what it cost when Obama took over, and almost twice what we’re spending on Iraq. Most allies aren’t interested in being part of any long-term plans. The Dutch have withdrawn their soldiers; Canada and Poland have expressed intentions to do likewise. The largest non-U.S. contingent is the almost 10,000 British troops, and new Prime Minister David Cameron has suggested he’d like to pull most of them out in the not-too-distant future.

There are two overarching elements that make the U.S. policy unpalatable: Public opinion keeps souring; most Americans now think the war isn’t winnable. And in contrast to the context surrounding the original adventure into Iraq, the United States is in tough shape financially, and there is a consensus that huge budget deficits have to be pared back.

Some of the most passionate supporters of the war, such as Republican Sen. John McCain of Arizona and Sen. Joseph Lieberman, a Connecticut independent, also advocate that all the tax cuts passed under the administration of President George W. Bush, including those for the wealthiest Americans, be extended. There is no mention of sacrifice.

Even many of these advocates acknowledge the war effort isn’t going well. Whether they are deploring the resurgent Taliban or corruption in the government of Afghan President Hamid Karzai, the most oft-cited villain, they proclaim, is Obama’s deadline to start withdrawing U.S. troops next summer. That supposedly has encouraged all sorts of bad behavior.

The problem is that it was the previous administration that told us the Taliban was essentially eradicated. Suddenly are we to believe they emerged phoenix-like after hearing that a troop drawdown would start in 2011? And do they really believe Karzai was a good-government democrat before Obama laid out his policy in a speech at West Point last year?

To be sure, just getting out, like 1989, is an option almost no one considers smart. The debate instead should focus on the particulars of a more limited counterterrorism policy that both prevents Afghanistan from being a safe haven again for al-Qaida and fosters stability in Pakistan, the more important question.

One option that’s not productive is a multiyear presence of 100,000 or more U.S. troops; the British and Russians could have told us that this turns into a counterproductive occupying force.

Watching Obama, Gordon Goldstein recalls the contrast that Bundy described in the 1960s between the skeptical Kennedy and more gung-ho, accepting Johnson on Vietnam. Bundy speculated that JFK, who believed that military means never should be deployed in pursuit of an indeterminate end, wouldn’t have engaged in a protracted war.

“Obama never drank the Kool-Aid on the counterinsurgency case; that’s why he gave McChrystal fewer troops than he wanted and set a date to start withdrawing,” Goldstein says. “This is illustrative of doubt and caution, of not wanting to be boxed in. That was Kennedy’s signature style on Vietnam.”

— Albert R. Hunt is the executive editor for Washington at Bloomberg News.