Among the various forms of tribute, including the pedestrians who stopped in their tracks, the sirens that wailed, and the workers who put down their tools to rest in silence, the more intrusive sign came from the blaring of car horns.

Such a demonstration wouldn't have been possible 12 years ago, when just 2.9 million privately owned cars filled the streets. Then, the clanging of construction instruments dropping to the floor would possibly have drowned out the relative peeping coming from the highways and roads.

Since 1996, the car-buying population, and the Chinese economy, has boomed, creating a middle class of eager car owners. Today there are 120 million privately owned cars in China, according to the Chinese state news agency Xinhua.

But in China, where the population is 1.3 billion strong, the car market is still tiny, just 4 percent of all drivers, according to Global Insight, which predicts the market will grow to 10 percent by 2015.

As that middle class grows, its voice may also be heard in demands for better regulation and enforcement of building codes that failed to protect schools from flattening onto thousands of children last week. That clamor will likely be louder than the horns.

--Laura Rich