Even before Sept. 11, Afghanistan's 27 million people faced a massive humanitarian emergency. Now, as large elements of the US military deploy toward Afghanistan in the search for Osama bin Laden, this deployment has cast an additional pall of fear over the country. Hundreds of thousands of Afghans have taken to the road, fleeing expected American attacks.

Any fear-fueled mass migration like this results in the deaths of the young and the weak. After 22 years of civil war and three years of near-famine, many Afghan civilians fall into those categories. The UN High Commission for Refugees is preparing for 1.5 million refugees who, it said, might soon join the scores of thousands already in neighboring countries. Others may never make it. Winter's coming, and the mountains are high.

What is America's responsibility? The Bush administration made a good start by sending generous shipments of food aid to the refugees outside Afghanistan. Now, it also needs to pay urgent attention to the needs of Afghan civilians still in the country. It should encourage as many families as possible to return to their homes, and assure the UN that it is safe for international aid workers who were pulled out of the country Sept. 12 to return.

To support these messages, President Bush should give crystal-clear instructions to the military to avoid "collateral" damage to civilians and their infrastructure during any operations in Afghanistan. The Afghan population is too vulnerable for us to treat their whole country as a "free-fire" zone.

In addition to assuring Afghan civilians that he is not targeting them, the president should also convey a solid American commitment to their long-term well-being. The fact that the US is already sending food aid to Afghanistan provides a good foundation for those assurances. Americans need to understand that this "failed state" will continue to pose a threat to global security unless, after the present confrontation, its economy and society can be rebuilt on a truly stable basis. In addition to the threat of terror, we should remember that no fewer than four of the nearby states that would likely compete for power in a failed Afghanistan have nuclear weapons.

But is it really America's job to help, post-victory, to rebuild Afghanistan? Well, not totally, since any such goal needs the help of others, too. But right now, Washington is leading the world in the tricky but urgent campaign to counter global terrorism. As it does so, it must also lead in defining - and working toward - the kind of world we want to see in terror's place. Ends and means are indeed related.

In any confrontation, planning for the post-victory needs to go with the effort of getting to that victory. That happened, with generally good results, in World War II. It did not happen so much during the cold war. And particularly, it did not happen regarding that key cold-war battleground, Afghanistan.

The West owes much to Afghanistan. The rugged anti-Soviet fighters there did a lot to puncture the war chest and morale of the Soviet military. Western governments eagerly showered money, advanced weapons, and landmines into the country in the 1980s, to help the mujahideen to fight the Soviets.

But after the mujahideen won, we turned our backs. The flow of Western aid virtually stopped, and we nearly ignored the needs of millions of Afghanis whose lives had been shattered by that 10-year war.

Now, such back-turning seems tragically short-sighted. America needs to reengage with Afghanistan. But we need to reengage in a smart and compassionate way. No, we should not leap right in and tell Afghans how to run their country - a recipe for disaster! But we can tell them - and demonstrate this through concrete actions - that we do not associate all Afghan people with the actions of their rulers or Mr. bin Laden.

Making such distinctions makes good political sense long term. And in the short term, acting to reassure and help the country's fear-filled citizenry will preserve the lives of thousands of noncombatants. Protecting the lives of innocents - isn't that what this "war" is all about?

Helena Cobban is a veteran journalist, and author of five books on international issues.