Route 3 Through Cambodia, China, Laos, Myanmar, Thailand, and Vietnam

Photo: Justin Mott for The International Herald Tribune

With trade across these borders increasing by double digits every year, China has helped build a series of roads inside the territory of its southern neighbors. The Chinese government is paying half the cost of a bridge over the Mekong River between Laos and Thailand, due for completion in 2011. It financed parts of Route 3 in Laos and refurbished roads in northern Myanmar, including the storied Burma Road used by the Allies in World War II to supply troops fighting the Japanese. China is also building an oil and gas pipeline from the Bay of Bengal through Myanmar to Kunming.

Taken together, these roads are breaking the isolation of the thinly inhabited upper reaches of Laos, Myanmar and Vietnam, areas that in recent decades languished because of wars, ethnic rivalries and heroin trafficking. The roads run through the heart of the Golden Triangle, the region that once produced 70 percent of the world's opium crop.

The invasions of new trade routes.... The Kunming-Bangkok route is especially fascinating given its history as fragmented opium routes and what it could mean in both benefits and costs for a poor country such as Laos.