Here's another article on the subject, that cites more research:
http://www.nytimes.com/2012/01/05/us/harder-for-americans-to-rise-from-lower-rungs.html?pagewanted=all&_r=0
Relevant quotes:
"At least five large studies in recent years have found the United States to be less mobile than comparable nations. A project led by Markus Jantti, an economist at a Swedish university, found that 42 percent of American men raised in the bottom fifth of incomes stay there as adults. That shows a level of persistent disadvantage much higher than in Denmark (25 percent) and Britain (30 percent) — a country famous for its class constraints.
Meanwhile, just 8 percent of American men at the bottom rose to the top fifth. That compares with 12 percent of the British and 14 percent of the Danes."
"Even by measures of relative mobility, Middle America remains fluid. About 36 percent of Americans raised in the middle fifth move up as adults, while 23 percent stay on the same rung and 41 percent move down, according to Pew research. The “stickiness” appears at the top and bottom, as affluent families transmit their advantages and poor families stay trapped."
"The United States maintains a thinner safety net than other rich countries, leaving more children vulnerable to debilitating hardships.
Poor Americans are also more likely than foreign peers to grow up with single mothers. That places them at an elevated risk of experiencing poverty and related problems, a point frequently made by Mr. Santorum, who surged into contention in the Iowa caucuses. The United States also has uniquely high incarceration rates, and a longer history of racial stratification than its peers."
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In other words, black people are only worse in total percentages as compared to race because more black people started off poorer than other races in the first place. They still basically follow the horrible mobility rates of America in general, which is particularly horrible when it comes to poor people escaping poverty. Blaming the issues on some internal community because of some quotes from people on television is basically missing the mountain for the molehill.