Charlton McIlwain is an associate professor of media, culture and communication at New York University. Jesse Jackson and Rush Limbaugh, Don Imus and Al Sharpton, Sen. Jeff Sessions and Sonia Sotomayor. Scarce is any pair more opposite than these. Yet this array of public figures share one thing in common: At one (sometimes many) times in their lives, they've all been labeled "racists." Clearly the term has come to mean different things to different people. It was not always this way, however. How did the meaning of "racism" and "racist" change so that it's now acceptable to apply the label to such a range of dissimilar people? And more important, what is the harm? The term "racism" originated in the 1930s, in the context of Nazi Germany's attempt to rid itself of the Jewish people - or race, as the Germans saw it. Consistent with the circumstances, racism referred quite narrowly to the pervasive pattern and practice of exerting power over and disenfranchising citizens because they were biologically different and, therefore, inferior. Racists were those who believed in the concept of racial inferiority and discriminated on that basis. In the late 1930s, the American political left began using these terms strategically, to identify pervasive racial problems and advocate government solutions to them. Further, the left contended, white people were responsible for racism not only because they initiated the institution of American slavery, but because they embraced the belief in black inferiority, on which it was built. In this view, black people (and other people of color) were innocent victims, perpetually disadvantaged by slavery and its aftermath. The civil rights movement made gains, in part, because the terms "racism" and "racist" were framed in this way. But in 1978, the landmark University of California versus Bakke case challenging racial quotas gave political conservatives their first substantial opportunity to redefine the terms. They initiated this linguistic sleight-of-hand by first invoking the once-scarcely used phrase: "reverse discrimination." Additionally, they linked this so-called reverse racism to the kinds of discrimination that the Civil Rights Act of 1964 intended to remedy. This made it easier to think of white people as victims, not just those who are responsible for or benefit from racism, and people of color (or a government that cowers to them) as those who can wield racial power. The next step in the redefinition of racism was to deploy the term "racist" as an epithet against racism's original victims. Many examples surfaced in the 2008 presidential election. Once, Barack Obama subtly criticized John McCain's campaign of using racial scare tactics. On another occasion - the infamous "dollar bill" statement - Obama pointed out that if elected, he would look different from every previous American president. In each instance, McCain's staff, supporters and conservative media personalities castigated Obama as a racist who "played the race card." More than half of Americans polled at the time believed Obama's dollar bill comment was, indeed, racist. What is the end result of this conservative effort to reframe racism and racists? Now, "racism" simply means acknowledging the racial distinctions apparent in American social life; "racists" are those who dare to publicly talk about them. When we speak of our contempt for racism and racists - almost everybody is afraid of the label - it no longer represents a call to find solutions to persistent racial problems. It simply reinforces the prohibition against making race part of our public deliberations - especially government's creation, interpretation and enforcement of law and public policy. A fact that Judge Sonia Sotomayor was reminded of every day this week.