Social Darwinism, a popular topic in the 19th and early 20th centuries, is making its way into modern American politics.

President Barack Obama invoked the theory this week to criticize his likely Republican presidential challenger, Mitt Romney, for embracing a new House GOP budget-slashing plan.

Obama argued that the plan was "thinly veiled social Darwinism."

But what exactly does the president mean? And will the theory's negative historical background be lost on most people?

For language expert Kathleen Hall Jamieson, social Darwinism seems like a risky term to use for political ammunition.

She says most people are familiar with Charles Darwin and his theory of evolution by natural selection _ survival of the fittest.

But Jamieson, a political communication authority at the University of Pennsylvania's Annenberg Center, explains that social Darwinism is a concept, an extension of Darwinism, that essentially says that those who are innately superior, often biologically superior, are advantaged in the conflict among or between groups.

She doesn't think that is what Obama is suggesting when he uses the term. Instead, what he is probably trying to convey is that he thinks Republicans subscribe to a theory that each person is on his own _ no help from others, no government help.

The term is loaded with all sorts of negative historical associations. It has ties in the past to the rationalization of inequality, says Jamieson, as well as to the eugenics movement and the idea that those who are unfit should not be allowed to propagate. Continued...