As the U.S. begins to extricate itself from the quagmire in Iraq, it is in jeopardy of plunging into a swamp in Afghani-stan that is filled with uncertainty.

Yet neither President Bush nor the leading candidates to succeed him, Republican John McCain and Democrat Barack Obama, who debated the Afghan issue last week, have so far articulated America's national interest in that landlocked Central Asian country. The White House, however, began a belated review last week of objectives and strategy in Afghanistan.

Gen. David McKiernan, the new commander of American forces in Afghanistan, sketched a gloomy picture for the Pentagon press on Oct. 1, saying it would take "four to five years" of intervention before the Afghans could take responsibility for their internal security.

"What I have found after four months in Afghanistan is that the environment there is even more complex than I would have thought," McKiernan said. "It's a country where they have experienced 30 straight years of war that's left a traumatized society and a traumatized tribal system."

Other soldiers with experience in Afghanistan have been even more pessimistic. Brigadier Mark Carleton-Smith, Britain's senior commander in Afghanistan, has said: "We're not going to win this war. It's about reducing it to a manageable level of insurgency that's not a strategic threat and can be managed by the Afghan army."

Carleton-Smith, who just finished a second tour in Afghan-istan, told the Sunday Times: "We want to change the nature of the debate from one where disputes are settled through the barrel of the gun to one where it is done through negotiations." Evidently, negotiations would include moderate members of the revived Taliban insurgents.

A U.S. Army colonel who led a task force in Afghanistan, Christopher Kolenda, writing in the Weekly Standard, asked: "How is it that we find ourselves unable to dispatch the Taliban seven years after their downfall? Winning in Afghan-istan requires us to understand the changed nature of the war we are fighting, and to adapt our strategy appropriately. Simply killing militants is not enough."

The insurgents, he said, "recruit from the vast pool of illiterate young men who see only continued poverty in the village and tribal status quo. The militants find their opportunity in the unraveling of the social and economic fabric since the Soviet invasion" of 1979.

T.X. Hammes, a retired Marine colonel and student of irregular warfare, has written: "In October of 2001, with 9/11 burned into the nation's consciousness, the Bush administration committed the United States to rooting al-Qaida out of Afghanistan."

Writing in the online Small Wars Journal, Hammes said after that fighting ended, "the effort in Afghanistan slipped from destroying al-Qaida to establishing a unified Afghan state." The Bush administration shifted focus to Iraq, he said, and "Afghanistan became an under-funded, forgotten backwater."

A retired Army lieutenant colonel, John Nagl, another student of wars like that in Af-ghanistan, wrote in the World Politics Review: "The good news is: We are now winning in Iraq. The bad news is: We are not winning in Afghanistan. The fact is that we have not had the level of thinking about the Afghan campaign that we have about the fight in Iraq. And we need that desperately."

Secretary of Defense Robert Gates, evidently miffed by these pessimistic views, told reporters traveling with him to Europe: "While we face significant challenges in Afghanistan, there certainly is no reason to be defeatist or to underestimate the opportunities to be successful in the long run.

"Part of the solution is strengthening the Afghan security forces," he said. "Part of the solution is reconciliation with people who are willing to work with the Afghan government." Gates suggested that the U.S. would negotiate with insurgents willing to work with the Afghan government.

A ray of light came from another British veteran of the Afghan wars, Brigadier Ed Butler, who told a U.S. Army historian that a tribe where he had been operating had worked out an agreement with the government in Kabul over "what the security measures would be, what the access was, who was going to govern, who would elect the chief of police and everything else."

All told, however, history is on the side of the skeptics. From the days of Alexander the Great about 325 B.C., through the Arabs, the Mongols twice, the British twice, and the Soviets from 1979 to 1989, Afghans have resisted and ultimately prevailed against foreign invaders.

Richard Halloran is a Honolulu-based journalist and former New York Times correspondent in Asia. His column appears weekly in Sunday's Focus section.