The L0 series magnetic-levitation train, developed by Central Japan Railway Co., moves along a test track near the control center during a trial run in Tsuru City, Japan, on Aug. 29, 2013. (Yuriko Nakao/Bloomberg)

The idea of getting from Washington to Manhattan in an hour on a floating train would seem a tad less fanciful if a similar system weren’t already being built in Japan.

That’s not to say the idea isn’t a serious stretch. Even the backers of a Washington company’s proposal to build a superconducting maglev train line concede the pervasive doubt.

“People dismiss it as unrealistic,” said former Pennsylvania governor Ed Rendell, who has been talking about speeding up trains along the East Coast since he was elected Philadelphia’s mayor in the early 1990s. “But I guarantee you when Lincoln talked about building the transcontinental railroad people said, ‘Are you crazy? You can’t get that over the Rockies!’”

In the car-loving context of the American transportation system, where political gridlock and scarce funding mire down many big ideas, there are countless questions. Among them: Which private investors will pony up for a magnetically levitated train that boosters say will cost $100 billion or more? How much will the federal government, already struggling to keep up with aging infrastructure, chip in? Can skittish residents in the train’s path be convinced, or at least bought off relatively affordably? Do American policy makers – and Americans themselves – have the inclination, and imagination, for such a venture? And can a nudge from one of the United States’ top allies make a difference?

Japanese Prime Minister Shinzo Abe is trying.

Caroline Kennedy, U.S. ambassador to Japan, left, speaks to Shinzo Abe, Japan's prime minister, as they sit on board the MAGLEV train undergoing testing at the Yamanashi Maglev Test Track in Tsuru City, Japan, on April 12. (Koji Sasahara/Via Bloomberg)

Abe pushed the proposal in a meeting this week with President Obama in Tokyo, and the Japanese government has offered a low-interest loan to finance up to half the $10 billion-plus first leg of a new maglev line from downtown Washington to Baltimore. That ride would take 15 minutes.

“I would love it. It would make my life a whole lot more comfortable,” said Marianne Matheny-Katz, an economist for the Army who commutes from Baltimore to Washington four days a week and stood in a snaking Amtrak line at Union Station Thursday. “Tonight I just want to get home fast. I’ve had a long week.”

The prime minister has touted the “dream technology.”

“It would free people from the congested roads that frazzle their nerves while saving not only 443,000 gallons of gasoline but also 682,000 hours of time that are now wasted annually,” Abe said last year at the New York Stock Exchange. The prime minister took America’s ambassador to Japan, Caroline Kennedy, for a 300-plus-mile-per-hour spin on the duck-nosed train earlier this month.

Japan has a 27-mile initial maglev line outside of Tokyo, and is slated to begin construction later this year on the rest of a privately financed 178-mile line between the capital and Japan’s third largest city, Nagoya, according to Yoshiro Taguchi, transportation counselor at Japan’s Embassy in Washington. Much of it will be underground and it is set to be completed by 2027, Taguchi said.

Plans also call for the line to be extended to Osaka by 2045, though there is pressure for that portion to be speeded up, Taguchi said. It will cost $54 billion to Nagoya, and another $36 billion to reach Osaka, Taguchi said.

Once completed, the American line would have a super express version – making one stop in Philadelphia and reaching New York in an hour. There would also be a slightly more local version with traditional East Coast stops in places like Baltimore, Wilmington and Newark. Each way, up to six trains can run per hour, with 1,000 people per train, Taguchi said.

YouTube video from The Northeast Maglev.

Wayne Rogers, a Naval Academy graduate and Maryland businessman who heads the Northeast Maglev, the Washington firm developing detailed plans for the line, said the United States should embrace maglev technology its scientists invented decades ago. “It’s time to deploy our ideas at home,” Rogers said.

The Central Japan Railway Company has agreed to transfer the technology — in which powerful magnetic forces lift and propel a train four inches above a U-shaped guideway that acts as an extended channel — “without charge,” Rogers said, adding that construction costs are only part of the picture.

“Many times we focus on the cost of doing something but ignore the cost of inaction,” Rogers said. “At $14.5 billion in lost productivity per year in our corridor and growing, these hidden costs need to be considered. . . .  Can we afford to do nothing?”

Rogers has sought to build bipartisan support with an advisory board that includes Rendell and former Democratic Senate Majority Leader Tom Daschle (S.D.) as well as former Republican governors Christine Todd Whitman (N.J.) and George Pataki (N.Y.), among others. He declined to offer a range of maglev ticket prices, though he said they “will be competitive with existing transit options.” The route is also yet to be determined.

Robert J. Puentes, director of the Metropolitan Infrastructure Initiative at the Brookings Institution, said the maglev train offers a concrete way to explore the realities of big, creative, and difficult ideas at a time when traditional U.S. government funding is tightly limited.

“We’ve talked about infrastructure in the abstract for too long,” Puentes said. Brookings is organizing a session next month with key American and Japanese players to wrestle with issues raised in the effort. “This represents a way to think about what kind of transportation infrastructure projects we need in the future. . . . There’s lots of interest in private sector investment in traditionally public-sector infrastructure.”

Amtrak says its Acela train travels at an average of speed of 83 miles per hour between Washington and New York, hitting a high of 135 mph and reaching Manhattan in about 2 hours, 45 minutes. Officials said the government-backed train system is working to purchase 28 new higher-speed trains, and has long-standing, multi-decade plans to build new rail-lines along the Northeast to ramp up train speeds.

“As the most knowledgeable and successful intercity passenger rail operator in the U.S., Amtrak is prepared to operate maglev trains as part of a coordinated intercity passenger rail system” whenever such a system exists, said spokeswoman Kimberly Woods. She added that Amtrak is “mindful” that such an effort “will face major funding and logistical obstacles that only a new paradigm in support for public transportation can address.”

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