Weeks from President Barack Obama's expected move to send more troops to Afghanistan, the consensus behind the US commitment there is crumbling as some raise the specter of a new Vietnam.
A growing number of experts doubt that the war can be won, while even Obama, who has already dispatched an additional 21,000 reinforcements there, contemplates a further troop increase and completes a strategic review.
On the campaign trail last year, Obama portrayed the war in Afghanistan as the only useful conflict in the war against terrorism. As president, he has called it a "war of necessity."
In March, the Obama administration redefined the war's goals, focusing on fighting Al-Qaeda and its supporters while demonstrating willingness to boost its military effort against a growing insurgency.
On the ground, the situation continues to deteriorate, with August the deadliest month for US forces since the war began in October 2001.
"It's a new strategy. It's the first one -- and I recognize we've been there over eight years," Chairman of the Joint Chiefs of Staff Admiral Michael Mullen told NBC television in August.
"But I also want to say that this is the first time we've really resourced a strategy on both the civilian and military side. So in certain ways, we are starting anew."
Mullen, the top US military officer, has been calling for fighting the "culture of poverty" deemed to favor the Taliban.
"But that (fight against poverty) took decades in just a few square miles of the South Bronx," countered George Will, a conservative columnist writing in The Washington Post who has called for the United States to "get out" of Afghanistan.
Wesley Clark, the former commander of the North Atlantic Treaty Organization, worried about the course of the conflict.
"The similarities to Vietnam are ominous," Clark wrote in the New York Daily News.
"There, too, an insurgency was led and supported from outside the borders of the state in which our troops were fighting. There, too, sanctuaries across international borders stymied US military efforts," the retired general said.
"There, too, broader political-strategic considerations weighed against military expansion of the conflict and forecast further struggles in the region."
Michael O'Hanlon, an expert who favors Obama's offensive strategy in Afghanistan, said critics need to better understand the strategy and developments on the ground.
"All they hear now is word of casualties, of our added troops making no difference so far, of (incumbent President Hamid) Karzai trying to steal the election, et cetera," O'Hanlon said.
"In Vietnam, we lost 5,000 or more Americans a year and the Vietnamese lost hundreds of thousands. In Afghanistan, we are losing 200 to 300 a year and the Afghans are losing a few thousand," the Brookings Institution analyst told AFP.
"However there is one disturbing parallel: the corruption in the respective indigenous governments and their general weakness."
In his commentary, Wesley Clark also drew a dire comparison.
As in Vietnam, "American public support slid away over time as our engagement ratcheted up and casualties mounted," Clark said.
Nearly six in 10 Americans are opposed to the Afghanistan war, according to a CNN/Opinion Research Corporation poll released this week.
A new front awaits Obama over the next few weeks in Congress, where dissonant voices are heard among fellow majority Democrats.
Obama, for now, enjoys support from a wide array of lawmakers, military officers and commentators. But all agree that the US task in Afghanistan is not only immense, but also immensely uncertain.