I entirely agree with Steven's excellent post, But can I raise an historical point that has been bugging me for a while (this might seem tangential, but there is a point to it).
Steven uses the kind of example that we find a lot in Theodore Allen and David Roediger's books, which create, it seems to me, a seamless history of racism that stretches from slavery to the present. Allen has it that the invention of the white race is something that happens more or less from the outset of the US. But that approach seems wrong to me. Rather, the history of race and racism is more discontinuous that continuous, and the white/black counterposition that seems today to be the exemplar of race, did not feature prominently in the politics of race in the Northern states in the early part of the century.
The politics of race in the 1890-1920 period, in the North at least, was largely a debate about immigrants from Southern and Eastern Europe, culminating in the nationality act with its 'Nordic' quotas. The big issue at the time was the growht of the northern cities. The enemy was the Jew, Italian and East European. In equal measure, people identified themselves in the cities, not primarily as white people, but as Jews, Italians and so on. At the point in history the ethnic identification was stronger.
None of this is meant to suggest that in any way racism against blacks was in anyway moderated, either in Northern enclaves like Harlem, or in the South - only htat the principle public race issue was about people who we would now call 'white')
Two generations later and those same people think of themselves primarily as white people. Increasingly they identify themselves in opposition to blacks, and their ethnic identification reduces in importance. Intriguing trends like Jewish solidarity with blacks disappears, and the current of radical Italians dries up. What happened?
The democratic party happened. The Democrats were reforged under Al Smith as principally the party that would represent the immigrant stock of the cities. As the Democrats succeeded, outsiders were brought in. Jews and East Europeans whose fathers had been persecuted and criminalised were brought into the Town Halls. An urban American identity is forged by a mixture of cajolery followed by acceptance. Growing to value their American citizenship first, the ethnic identity falls away. Fighting in the 2WW consolidates this patriotism.
That American patriotism is the basis of white racism. But the Southern model of white-black conflict could not be reproduced in the North until newly forged 'White' Americans defined themselves in opposition to blacks. That happened with the twin movements of the Black migration North and the White flight into the suburbs. When third generation Italians, Jews and others fled the cities to avoid the black urbanisation, they took on the identity of white Americans.
When Martin Luther King moved the civil right campaign to the suburbs of Chicago, he met the limits of reform. He was confronted by crowds of white Americans waving the Southern Cross - actively aping the white identity of the South. But those white's granparents were also the subject of a race campaign, supported by the Ku Klux Klan, against the urban immigrants and consolidated in the quotas acts of the twenties.
The white race was not just invented once, but reinvented a second time in the period 1930-1950. -- Jim heartfield