It's becoming a bit of a running gag in the transportation community: President Obama is one of the loudest supporters for spending money on improving the nation's infrastructure. But when it comes to saying how the country should pay for it, he's surprisingly quiet.

This month Obama continued that tradition, proposing a plan during his State of the Union speech that would focus on creating jobs by spending $50 billion on infrastructure in urgent need of upgrades. But when the White House released more details about the plan a few days later, it failed to mention a funding mechanism. The move wasn't a surprise, but it was unusual given the feds focus on reducing the deficit.

Obama had previously proposed a $50 billion infrastructure investment in 2011 -- it didn't go anywhere -- and his budgets have regularly proposed huge transportation investments funded by "peace dividends," a mechanism that most observers in the transportation community say isn't real money. This has caused many transportation stakeholders and experts to ask whether they should even place stock in the White House's infrastructure rhetoric.

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"The fact of the matter is I think it is a harmful thing, the way they keep putting this proposal out there year after year, because they don't really have a realistic way to finance it," says Jack Schenendorf, an attorney who spent 25 years on the staff of the House Transportation and Infrastructure Committee. "It really turns into a mirage, kind of. I don't think that's helpful."

John Horsley, the recently retired head of the American Association of State Highway and Transportation Officials, says that in the past, transportation leaders have hung on the president's every word during the annual State of the Union speech, hoping for just a passing reference to infrastructure. In that regard, Obama's frequent mentions of infrastructure have been useful. But, he adds, substantive policy discussions of the issue appear lacking. "It's good that he's rhetorically addressing it," Horsley says. "I think everyone is frustrated with the lack of real dialogue taking place between the administration, the House and the Senate on an issue like this."

The president's push for a multibillion-dollar infrastructure investment comes at an interesting time. After years of inaction, Congress finally passed a highway bill last year that relied on some creative accounting just to ensure level funding for the program. While transportation advocates have been calling for an increase in the gas tax -- including the influential U.S. Chamber of Commerce -- hardly any Washington lawmakers, including the president, have echoed that call.

There are also questions about why Obama would propose a one-time infrastructure investment today when, just a few months ago, he was largely disengaged from the passage of the highway bill -- a long-term bill that federal agencies are just now working to implement. Janet Kavinoky, who leads the U.S. Chamber of Commerce's infrastructure efforts, praised the president for his comments but says a comprehensive, long-term plan would be more effective than a separate, one-off infrastructure program developed alongside it. "That's sort of a prescription for duplication and waste," she says.

Still, others say the president's lack of details may have been intentional. Former U.S. Rep. Jim Oberstar of Minnesota, a past chair of the House Transportation and Infrastructure Committee, says the president's speech is significant because it's clear that he genuinely values transportation infrastructure. He specifically praised the president for calling out the need to invest in repairs to the country's thousands of "structurally deficient bridges. "That is a phrase that only infrastructure junkies use," Oberstar says.

Oberstar -- who some members of Congress have endorsed for transportation secretary -- says he's encouraged by the president's apparent willingness to partner with the private sector. Just last week, the White House reiterated the president's desire for a national infrastructure bank that has a private component, as well as something it dubs the "Rebuild America Partnership," which is a vaguely defined plan to "partner federal, state and local governments with businesses and private capital to provide America with the best transportation, electric, water and communications networks in the world."

"What I see is an evolving plan," Oberstar says.

For now, it's not exactly clear that the proposals carry any real weight. But the public should know soon. Whether the president's upcoming budget contains detailed funding proposals, and the type of person he appoints as transportation secretary, could both be important signals. Pete Ruane, CEO of the American Road & Transportation Builders Association, says the president could risk losing credibility in the transportation community if he doesn't follow up on the ideas he pitches. But for now, Ruane says, he's cautiously optimistic. "We need some specific ideas," he says. "That's what leadership is all about."

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