High-speed rail is commonplace in many other countries. Will it track in the U.S.?

With high-speed rail ambitions in California delayed by years and coming in at a higher-than-expected cost, Lou Thompson, who sat on the state's high-speed rail peer review group, said "failure is always an option."

He doesn't think failure is what will necessarily happen in California, but earlier ambitions have been scaled back. When California voters approved a bullet train between Los Angeles and San Francisco in 2008, the estimated price tag was $33 billion, with a target completion date of 2020. Nearly two decades later, the California High-Speed Rail Authority is preparing to lay its first tracks to connect Bakersfield and Merced — a portion of the original route — with a target completion of 2033.