Across the country, transportation and utility department directors are repairing roads, extending sewers and building water lines. Other officials are managing airports, libraries, parks, police and fire departments. This is the daily, weekly and monthly life of city and state government, managing these essential but ordinary assets.

 What’s interesting is that once upon a time all these services weren’t just accepted, but were seen as mere dreams. They were aspirations, which some people shared and others thought foolish and unwise. Public water systems were a wild idea in the mid-19th century. The construction of the secondary road system in the early 20th century was an immense task, with dozens of bureaucratic battles and choices. The idea of every city having a library was a pipedream until Andrew Carnegie spent a chunk of his immense fortune to build about a thousand of them more than 100 years ago. Even the idea that every child was entitled to an education at public expense was once controversial and a much debated notion (and one that wasn’t fully settled until well into the 20th century).

But here’s what’s troubling me now. I don’t see many aspirational infrastructure movements today. True, the livable streets movement, which envisions transforming our city streets into places where people can walk, bike, stroll and drive, is clearly aspirational. Its proponents are selling a vision, which some share and others oppose. Even high-speed rail is an aspirational movement. Its proponents see families one day zipping between cities at unbelievable speeds and stepping off trains into vital and active city streets. And the cities and states that are building fiber-optic and broadband networks themselves, such as Minnesota or Burlington, Vt., are aspiring to something.

But those movements don’t translate into any kind of national vision. Foreign countries, meanwhile, are engaged in just the kind of infrastructure dreaming we need here at home. China, Korea and other Asian nations are building national networks for high-speed trains and ultra-fast broadband services. The European Union (EU), although quiescent a bit during the ongoing economic crisis, is building soaring bridges that with their architecture express a combined dream of beauty and utility. The EU is also planning state-of-the-art train networks into new member countries such as Bulgaria and Romania.

Here in the United States, private companies like Google and Amazon are very active. Technological marvels are unveiled almost daily. But the public sector has to be involved and ideally in charge for a vision to be a comprehensive one. That’s hard to see right now. It is true that, after a long battle, we have the rudiments of a national health-care plan. This is a type of infrastructure, and the questions of how and whether to extend health care are the sort of aspiring battle we should engage in as a society.

If we are to move toward a big new public works program, we need to be doing a few things. One is to avoid thinking of or describing public works as simply a weighing of costs and benefits. Among infrastructure professionals, there has long been a chant that the politicians and, implicitly, the people should stand back and let the experts decide. Let rationality reign, they say; keep politics out of infrastructure choices.

But of course, infrastructure is all about politics, and should be. When you build infrastructure, you’re not just solving a problem, you’re creating a new reality. Numbers, even if accurate, often can’t answer the big questions, like what kind of world do we want to live in, who benefits and who’s in control? These debates are ones of values, and they can’t and shouldn’t be neutralized by technocrats.

When Congress in the 1950s approved the Interstate Highway System, a massively flawed project in my opinion (but a bold one), it wasn’t just solving a traffic congestion problem; it was approving a vision of a country where families in cars could pleasantly go from place to place from their new suburban homes.

If the United States ever builds true high-speed rail lines, and catches up to the rest of the world, it will happen because someone paints a bold vision, and citizens start to see it. Planners and politicians should not shy away from such rhetoric. President Obama had the right idea when he pledged in his 2011 inaugural address to put high-speed rail within reach of 80 percent of Americans within a generation. This is the kind of aspirational language that is needed to build new and ambitious public works.

I’m not against numbers. Sure, do plans and cost-benefit evaluations. We need to weed out dumb projects that have fuzzy missions and poor design. But be aware that formulas can’t show everything. For one thing, they can’t capture passion. That’s what wins at the end of the day: A vision of how things could be, and citizens who see it.