One of the little-noted casualties of Sept. 11 was an elaborate plan in Washington to celebrate the 40th anniversary of the Peace Corps. The celebration, scheduled for nine days after the terrorist attack, was canceled.

But why celebrate the Peace Corps at all? What did it ever do to achieve peace? Why has anti-Americanism flourished, even after our nation sent 140,000 of its "best and brightest" to spread goodwill? How many American volunteers served in Afghanistan? What did they ever teach the rest of us about this complex Muslim culture? What did the Peace Corps volunteers ever teach the fundamentalist Taliban about us, if they hate us so?

I have more than a casual interest in these questions. Just as I graduated from college, I heard the stirring words of President Kennedy: " ... ask not what your country can do for you; ask what you can do for your country." A few months into this grand experiment, I became a Peace Corps volunteer, and it changed my life.

Nearly 40 years later, I am neither wise nor cynical about my own service, and I respect the efforts of my Peace Corps colleagues, failed or otherwise.

We have tasted deeply of other cultures. We love America, yet we are comfortable citizens of the world. We are people with a mission. This mission is what our nation must now heed in its battle against terrorism.

After I struggled to teach English in Ethiopia without books for two years, some of my students managed to get good scores on the national school-leaving exam. Quite a few became refugees and now live in the U.S. A larger number were killed in the generation-long war between Ethiopia and Eritrea. Some survived and became leaders of the newly independent nation of Eritrea.

Here is how you measure success in the Peace Corps: I established a small library with books sent from the United States. Years after I left Ethiopia, a nomad child picked up one of these books, a math text, and discovered that he had a talent with numbers. He is a committed Muslim and grew up among extremists in Sudan. He could have grown up to be a terrorist. Instead, he is a math professor in Toronto; he tracked me down on the Internet.

What is this small voice that keeps the Peace Corps mission alive? It is the stench and buzzing flies of poverty, seared into our consciences. It is the hope that the lessons we taught and the lessons we learned will tip the balance toward self-sufficiency for proud and resourceful people. It is the conviction that guns, flooding the world in such quantities that their price is cheaper than bread, will solve nothing for the weak or the strong.

It is our respect for local traditions: the Sharia courts, the village headmen sitting under spreading olive trees, the lilting stories and songs of our new languages--Urdu, Tamil, Swahili, Amharic, Arabic--that make us believe that peace is possible. The "other" is no longer strange, weird or threatening.

There comes a point in every war when people on all sides grow tired of killing. They accept the undeniable fact that their common humanity is more fundamental than what separates them. This defining moment is called peace.

Every Peace Corps volunteer has witnessed this alchemy of the exotic becoming familiar. This experience--and the belief that it can happen again and again, even among those who are most hostile to our nation--is what eventually will make America secure.