Amid the high drama of fiscal brinkmanship in Washington, it’s easy to forget that reducing budget deficits isn’t the biggest economic challenge we face. Even more important is kick-starting the great American job machine and reversing our country’s slide in global competition.

Critical to both goals is shoring up the decaying physical foundations of national prosperity. Without world-class infrastructure, the United States won’t be able to attract private investment, sustain rapid technological innovation and productivity growth, or keep good jobs from going overseas.

According to a new Gallup poll, general economic concerns (35 percent) and unemployment (22 percent) top voters list of worries, with federal deficits and debt a distant third at 12 percent. Fiscal restraint is important, but it must be balanced against the larger imperatives of jobs and global competition. Among other things, this means leaving room for public investment to replenish the nation’s stock of physical capital.

America can’t build a more dynamic and globally competitive economy on the legacy infrastructure of the 20th Century. Thanks to their parents’ far-sighted public investments, baby boomers grew up in a country that set the world standard for modern infrastructure. But after a generation of underinvestment, compounded by politicized spending decisions, we now face a massive infrastructure deficit that exerts a severe drag on U.S. productivity.

Meanwhile, China and other fast-rising countries are building gleaming new airports and bullet trains. To keep from falling farther behind, the United States needs to make large-scale capital investments in repairing decrepit roads and bridges; upgrading air and sea ports; building “intelligent” transportation systems and smart energy grids; modernizing the air traffic control system; speeding up our pokey rail networks; and leading the world in deploying ultra-fast broadband.

But with the government strapped for cash, it’s reasonable to ask where the money to rebuild America will come from. The answer is that we need to look more to the private sector. U.S. companies are sitting on $2 trillion in idle cash, and pension funds, overseas investors and sovereign wealth funds also are looking for places to invest. Although the federal government will have to put up seed capital, its main role should be to leverage private investment in state-of-the-art infrastructure.

That’s why America needs a National Infrastructure Bank. As proposed by the bipartisan trio of Senators John Kerry, Kay Bailey Hutchison and Mark Warner, the bank would use a modest, one-time appropriation of $10 billion to leverage enormous investments — $640 billion over 10 years — for projects with the greatest potential to put Americans to work and enhance U.S. competitiveness.

President Obama has repeatedly endorsed a national infrastructure bank and proposed the idea again in the budget he sent to Congress in February. But the Senate bill (and a separate House proposal championed by Rep. Rosa DeLauro) have decided advantages over President Obama’s proposal. The president’s approach starts with a smart idea to create programs that work more with the private sector to find financing solutions. But unlike the Kerry proposal, it does not focus enough on the most powerful tools for leveraging private investment: loan programs that include a reasonable cap on the federal share of project costs. Obama’s bank would also be housed within the Department of Transportation, whereas the Kerry bill would make the bank an independent, quasi-public entity. That’s an important difference, because to attract hard-headed capitalists who expect a real economic return on their investments, the government’s financing facility must be genuinely free of political interference.

An independent infrastructure bank would select projects based on their ability to generate real economic returns rather than their influential political patrons. As a self-sustaining entity that would not rely on future appropriations from Congress, the bank would not be subject to the pork barreling and earmarking that distorts federal and state infrastructure spending, especially on transportation.

It’s time to get serious about our dilemma: the U.S. economy is creating too few jobs to bring down unemployment to pre-recession levels. For that, we’d need nearly 12 million new jobs, or about 100,000 more on average than the 200,000 the economy is creating each month. Big capital projects would immediately create those jobs where they are most desperately needed–in the hard-hit construction industry, which is still struggling with a 20 percent unemployment rate.

In the short run, a big national push to build modern infrastructure could create high-skill jobs that can’t be exported. In the long run, it will ensure America’s return to being an engine of production, not just a global center for consumption. That’s why, as Congress struggles to contain federal deficits and debt, it needs to make room for a National Infrastructure Bank to rebuild America.

This item is cross-posted at the Huffington Post.