Hardship has built a stronghold in the American suburbs. Whatever image they had as places of affluence and stability was badly shaken last year, when reports analyzing the 2010 census made it clear that the suburbs were getting poorer.

While the overall suburban population grew slightly during the previous decade, the number of people living below the poverty line in the suburbs grew by 66 percent, compared with 47 percent in cities. The trend quickened when the Great Recession hit, as home foreclosures and unemployment surged. In 2010, 18.9 million suburban Americans were living below the poverty line, up from 11.3 million in 2000.

It is possible to see this struggle just beyond New York City in a quintessentially suburban place, Long Island. There have long been pockets of poverty there, created by race and income segregation. But it is not just in pockets anymore. These days the struggle has metastasized: foreclosed homes are just as empty in the better-off subdivisions, with the same weed-choked yards, plywood windows and mold-streaked clapboard siding.

Long Island’s two counties, Nassau and Suffolk, have the second- and third-highest foreclosure rates in New York State, behind Queens. Debt counselors across the island juggle a mix of clients: immigrant families undone by predatory lenders and middle-class professionals impoverished by illness, layoffs or credit-card bills. Families who once donated food now wait in line to receive it at pantries that empty out week after week. Homeless women with children move in with relatives or into motels, the government-paid shelters of last resort.