When it was built in 1936, the San Francisco-Oakland Bay Bridge was a Depression-era project that put scores of Americans to work. When its $6.3 billion replacement opens in two years, it will be an international affair from the bottom up, an example of massive outsourcing that has drawn both praise and criticism. Half a dozen countries contributed expertise or materials, none more so than China. "China was immensely helpful to getting this project built," says California Department of Transportation spokesman Bart Ney. "They were able to turn the steel around and work directly with our own inspectors to make...