In 1963, Paul Theroux joined the Peace Corps, shaping both its future and his view of the world: Cue President Obama's new appeal to public service...

I became a teacher in Africa and my whole life changed. I was happier, I had a purpose, and no one ever asked me, "What are you going to do with your life?" I had left home. I was becoming the person I wanted to be, not just a young man with a job but someone developing a sensibility. I had volunteered because I wanted to know the world and myself better.

The route from New York to my destination, Nyasaland, took in Rome, Ben-ghazi (Libya), Nairobi, Salisbury (Rhodesia), and finally the tiny aerodrome at Blantyre. Flying low into that last stop, I could see tiny thatched-roof mud huts surrounded by banana groves and maize fields. This sight lifted my spirits. The thrill was intensely like being on another planet. In some ways it was just as remote, a parallel universe, but I thought of it as my Eden.

It was December 1963, and I was glad to be gone. I'd been dismayed by the spirit of the times, the violence, the complacency, the racism, the militarism, the weird quest for material goods. I was well aware, with a lightness of soul, that I was unburdened. Everything I owned in the world fitted into the small suitcase I had with me. I had nothing in the bank, no property; did not own so much as a chair. I was superbly portable. I had just turned twenty-two.

That first departure for Africa led me to a lifetime of travel. It shaped the way I see the world and showed me that there was more to write about than my own inner miseries. I realized that what at first seemed so alien—a schoolhouse of barefoot students at the end of a red clay road—was not so different at all. Wishing to express this experience, I became a writer.

Although I joined one of the earliest Peace Corps groups to go overseas, I was not heeding the call from President John F. Kennedy. Apart from being a coastal New Englander, as he was, I felt I had nothing in common with this remote figure or the complexities of his ambitious and ruthless family. I joined instead partly because the Peace Corps was committed to helping people who were at last free from colonial control. As for the rest, it was a leap in the dark.

Today, we live in a world much like the one I knew as an absolute beginner, more than forty years ago. Technology is brighter now, but so what? Bewilderment persists, we're as fallible as ever, and most thoughtful people, especially the young, have the same question: Where is my place in the world?

Once again we have a president who is calling on us to engage with our community and the world. Just as then, we face war and violence—this time in Iraq, Afghanistan, and the Middle East. What's new is the prospect of global economic collapse: Hard times can divide us, or they can help us to understand each other better. In such fragmented times, finding the connections among us seems more urgent than ever. Travel—not sightseeing, but real encounters with real people—has never mattered more in helping us to see how we're crowding a blighted planet, how interdependent we are.