FORTUNE – My most prized possession is my passport — its bulging, brown-edged pages a result of time spent in dusty places and of many hands touching it. Hands like those of the young Iranian customs official who paged through it, reviewing every country I’d visited. “Our friends!” he said of Yemen. Then, with a bemused smile he asked, “Why do you go to these places?”
I used to have the goal of visiting 100 countries and all 50 states in my lifetime. Five years ago that seemed unattainable. But I’ve been lucky in my job as a journalist: I travel for a living. I’ve met friends who open my eyes to situations and stories I’d never understand had I stayed home. Now, with 76 national “stamps” and 42 states, I’m on my way.
I have an inspiration on this quest. When I was young, my great-uncle sent me postcards from all around the world. Cousin John, as we called him, spent time in Shanghai during his childhood in the 1920s and served in the U.S. Navy. As a child (back then I didn’t imagine becoming a reporter — I dreamed of joining the CIA), I’d listen to him during his visits as he spent hours sitting on the sofa and telling me about every picture in his latest photo album. It turned out that he kept an annual log of every country and city he had visited.
When he died a few years ago, someone in our family discovered his list and sent it to me. I treasure it. I read it often, enjoying the precise and artistic handwriting of the precomputer era and his notation of even the small trips (he catalogued every visit to my childhood home, which was only two hours away).
I believe that traveling for work and personal relaxation is one of the greatest luxuries on earth. And I hope that more people can experience it. According to the U.S. Travel Association, only 30% of Americans have passports today. More than half of Americans’ international trips are to Mexico and Canada.
I also like visiting our NAFTA partners and border siblings. But traveling to even more far-flung places has fulfilled me personally, and I think America should prioritize travel early in its citizens’ lives: Service trips for teens during summer vacations would be one way to do that.
Travel has also fueled my career. And it isn’t just journalists and ambitious oil company employees who need to travel. Try aiming for a top job at, say, Apple (AAPL) if you haven’t spent time overseas. According to Piper Jaffray, more than half the iPhones and Macs sold last year were purchased by consumers outside the U.S., and iPads are about to cross that threshold. (When CEO Tim Cook first arrived at Apple, he met with his team to discuss a problem in Asia. “Someone should be in China driving this,” he told the group, according to a 2008 Fortune article. Thirty minutes later he turned to one of his key lieutenants and asked, “Why are you still here?” You can bet that guy had a passport.)
Cousin John taught me something else worth sharing in this retirement issue. He didn’t have a spouse, so he always traveled alone, even in his late seventies. Being alone meant he met more people — and he stayed in touch with them. I credit him with my journalistic urge to talk to strangers and my confidence in traveling alone — something I’ve done at various points in my life to places like the Amazon, Cambodia, and Japan.
By the time I retire, I hope I will have reached my 100-country milestone, freeing me up to return to some of my favorite places with time to stop at roadside stands instead of cramming in every sight. For now, I dream of spending a year in Tunisia. Tunis stole my heart. Nearby are some of the most incredible ruins of the Roman Empire, and sets and landscapes from the Star Wars movies. I drove around the country as the revolution hit last year. I can only imagine what it will be like when I retire. Until then, I’m going to keep exploring, thanks to my kindred spirit Cousin John, who, come to think of it, might have been the CIA agent I once envisioned becoming.
This story is from the July 12, 2012 issue of Fortune.
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