California's proposed bullet train will need to soar over small towns on towering viaducts, split rich farm fields diagonally and burrow for miles under mountains for a simple reason: It has no time to spare.
In the fine print of a 2008 voter-approved measure funding the project was a little-noticed requirement that trains be able to rocket from Union Station in downtown Los Angeles to San Francisco in no more than two hours and 40 minutes.
It was an aggressive goal, requiring cutting-edge technology, and was originally intended to protect the sanctity of the bullet train concept from political compromise. Whether the California High Speed Rail Authority can meet such a schedule is far from certain. Even some backers of the project now say it was a mistake to lock in the strict requirement.