Housing Choice vouchers, administered through the Department of Housing and Urban Development and local agencies, offer what shelters and charity don't: stability and permanence, argues the Center:

Housing vouchers are flexible, cost-effective, and successful in making rental housing affordable even for families with very low incomes, and numerous studies show they can play a critical role in reducing homelessness among families with children. Because families can use vouchers almost immediately, vouchers can rapidly address rental housing needs when homelessness is rising.

From 2003 to 2007, according to the analysis, Congress stopped funding new vouchers, after incremental increases over the previous roughly 25 years. The same period saw the snowballing of the foreclosure crisis as well as a 25 percent increase in the number of poor households devoting at least half of their income toward housing.

The roughly two million low-income families lucky enough to have vouchers represent the racial dimension of the housing crisis. In many cities, according to Harvard's DiversityData project, people of color are starkly overrepresented. Blacks and Latinos make up roughly 80 percent of voucher holders in New York City, and in Miami, 95 percent.

Still, voucher rental assistance alone won't resolve the housing crisis, since the government ultimately has to build more affordable housing stock across the country. Moreover, the voucher program's mission of promoting integration and countering housing discrimination has in many respects failed.

But until federal housing policy is revamped, many houses and apartments (including, potentially, a massive number of units left vacant by foreclosure) are sitting empty, while streets and shelters teem with dispossessed families. It's the paradox of an overinflated housing market that squeezes out the neediest. Vouchers help correct that imbalance in the short term, and could lay the groundwork for a housing system aligned with real need instead of speculative fiction.