The damage from Friday's earthquake and tsunami is horrific. But the disaster could surely have been worse without the heavy preparations Japan has made over the years. The Japanese have invested heavily in infrastructure and buildings designed to withstand quakes. To better understand the structural precautions Japan had in place and whether the U.S. employs similar technology and building codes, host Robert Siegel talks with Stephen Mahin. Mahin is a professor of structural engineering at the University of California, Berkeley and the director of the Pacific Earthquake Engineering Research Center.