One of Teddy Roosevelt's visions for the 20th century was a waterway between the Atlantic and Pacific oceans. Under his presidency, construction on the Panama Canal began in 1904. Completed 10 years later, the passage rendered the long voyage around the tip of South America unnecessary dramatically reducing shipping times and costs. Since then, the canal has profoundly re-shaped the face of commerce on our planet.

The land divided, 233 million tons of cargo passed through the isthmus in 2007. Roughly 20% of these tons represent the amount of grains, canned and refrigerated foods, and other agricultural commodities that were shipped between the oceans last year. Our dinners, packaged in uniform steel shipping containers whose temperature and humidity are controlled via satellite by watchful technicians, pass quietly through the calm waters of the canal - a respite from the rigor of the two seas.

Kiyah and I returned this week from a short trip to storied Panama. We went to visit a close friend living in the canal zone hammering out the details of his dissertation research. Our first night, Ashley took us to the Miraflores locks to experience the gentle lowering of the ships into the Pacific. It was like watching the heart of a great organism steadily pumping the lifeblood of a world system.

In the week that followed we sampled much of Panama's produce and seafood, scoured the local markets and supermarkets, plodded through rain and forest to discover the tropics, and marveled at the attending squalor and splendor of Latin American lives.

This caused me to think.

For all its precision in transporting goods in two directions, the Canal has failed to do so with wealth. For decades now, consumers in the developed world have enjoyed the fruits of a global commerce which has delivered to their neighborhoods the flavors and textures of the world. Our diets have become global as have our expectations. Many in the developing world, however, have not shared in this fortune. Their gardens and farm-plots have not given way to progress. Their diets have remained local. These things, however, may be changing - especially in Panama.

The craze of eating locally, which has become established in the U.S. and Europe, is now challenging our expectations and re-casting our diets... at least some of our diets. My impression is that this change is being embraced largely by those with the means to embrace it. Those with a few extra bucks. Those with the time to see the great value in it.

Curiously, at the same time that the fortunates in the west are turning back to the land and back to their communities for sustenance, the burgeoning economies of many developing countries, including Panama, are sitting down at the global table and demanding to be served. The question remains that as these people strive for their deserved taste of the good life, are they trading in their carrots and avocadoes for soda and sugar cereal?

The complexity of these issues is enough to give pause - long pause. Some would argue that the dietary transition of the have-nots has not been a choice but an imposition as global food companies have looked to conquer new markets. I would not disagree...

At a supermarket in the city, a young well-to-do mother reaches for a shiny box of flakes - the object of her child's tantrum. Should somebody tell her they're not so great?