A quick quiz for this holiday season: What portion of our country's gross national product might it be appropriate for Americans to devote to helping poor countries develop? One percent? Maybe a third or a half of that?

Here's the actual portion for 1999: one-tenth of 1 percent.

This is tiny, but not anything new. It's the end point of a decades-long process of congressional cutbacks - with successive administrations going along. In 1970, aid was three-tenths of 1 percent. In 1990, two-tenths.

Now, as an urgent part of our antiterror campaign, Congress and the executive must work quickly to jack aid up considerably. The United Nations is asking rich countries to allocate 0.7 percent of their GNP to overseas development aid. We should aim at getting close to that goal - fast!

Our aid's 30-year decline has not served American interests well. The shockingly low level of aid throughout the 1990s prepared the ground for the kind of chaos and social despair in which the Taliban, Al Qaeda, and their ilk have flourished. This is not to excuse those groups' actions. But their operatives were able to organize their hate-filled acts undisturbed while living in communities that didn't feel like they had much stake in a world system that seemed to treat them so poorly.

President Bush is right to pledge that the United States will not "walk away" from the needs of Afghanistan's people, as it seemed to in the early '90s. But the problem is far broader than Afghanistan. Hundreds of millions of people live in failed and failing states around the world. Many feel they have little stake in the stability of the world system. If we want to prevent those countries from continuing to incubate desperation and cruelty, we need to think soberly about how to give those people such a stake.

That will take, among other things, a sustained investment in overseas development aid. The needs seem most pressing in Afghanistan, which could fall back into warlordism, opium production, and terrorism if we and other donors turn our backs again. But it is also urgent in 15 to 20 other countries. Many are in Africa; some are already accused of having links to Al Qaeda.

Regarding Afghanistan, UN development chief Mark Malloch Brown has stressed that aid donors need to prepare for a long-term commitment to national rebuilding - as well as "instant" donations to meet urgent needs. After a recent visit to Afghanistan, he said, "I have a sense of a great national U-turn at the grassroots level; of ordinary Afghans rejecting the cycle of war and decline, and wanting to seize this moment to make a nation where their kids - girls and boys - can go to school; where mothers and fathers can go to work in the mornings and expect to come home in the evening ... without threat of violence."

Mr. Malloch Brown listed four priorities in Afghan rebuilding: security, agriculture, community-based programs, and the return of displaced persons. He said the UN would present a five-year recovery plan to a donors' conference in Tokyo in January - and he noted that the latter years of that program would be the more expensive ones. Development experts warn that the US and other donors must be ready to stay the course in Afghanistan - and that the funds for this must not come out of those already earmarked for Africa.

Can the UN "deliver" on organizing rebuilding programs in failed and failing states? Treasury Secretary Paul O'Neill has cast doubt on the effectiveness of development aid. I wonder if he's ever been to a country like, say, Mozambique, a very poor country that is still recovering from a long and brutal civil war that ended in 1992. That war killed a million of Mozambique's 16 million people, displaced 5 or 6 million more, and caused massive infrastructure degradation that led to long years of drought and famine.

I was in Mozambique last August. Eight years into a UN-led rebuilding effort, it's still poor. But I saw how much its people have already benefited from programs similar to what Malloch Brown is proposing for Afghanistan. In addition, the UN ran special programs to reclaim roads and arable land from land mines, and to support the demobilization and reintegration into civilian life of former combatants. (Afghanistan could benefit from programs like that, too.)

Is Mozambique a reported haven for global terrorists? No. Do most Mozambicans feel they have a stake, however small, in global stability? Probably so.

I'll admit, there have been failures in UN rebuilding efforts, as well as successes. Turning from war to peace and stability has to be a people's choice. But if we structure the incentives wisely - which we did far too rarely during the "stingy '90s" - most folks around the world will make the right decision. Just as they did in Western Europe, in the late 1940s, when the Marshall Plan invested one-fourth of 1 percent of US GNP, every year for four years, in postwar recovery and reconstruction.

Now we must plan once again to invest seriously in peace.

It's true, our economic prospects look murky. But we're still a rich country. All the world's other rich countries invest a considerably larger portion of their GNP in overseas aid than we do. There are scores of ways our budgeters could find the money to bring our aid figures up - including deferring tax cuts or paring back some of the planned growth in military spending.

If the starving, war-ravaged Afghans can make a U-turn toward peace, can't we Americans support them and the world's other very-low-income folks by making our own U-turn on aid? The time to do that is now.