fear of an angry black man

Rather than spend my time creating talking points for an upcoming lobbying campaign at work, I'll jot down some random questions in the wake of the speech Obama gave today (which were in reaction to the public reaction to some old Jeremiah Wright comments.)

Primarily, my questions are about mainstream (i.e., white) reaction to black anger and I'll try to keep these as succinct as possible.

Why, whether expressed in the way that Wright had done, in the comedy of Dave Chappell or the comic strips of Aaron MacGruder, do folks have such strong reactions to black socio-political anger?

What, and who, is served by the public pressure for Obama (or any black person) to distance himself from the problematic comments like the ones Wright made (or even the ones made by Farrakhan)?

What fears are assuaged once this distancing has happened and, conversely, what fears are stoked when a black person refuses?

What allegiances are being sought through this kind of pressure?

Why must people of color perform this kind of dance when individual white people don't? (For instance, we have yet to see any kind of thorough, well-wrought distancing from Hillary Clinton after Ferarro's avowedly pro-white comments were made.)

And why does the word 'minstrelsy' come to mind?