Killing change, that's what people vested in the status quo try to do.  Or at least threaten to do, and everything up to and leading.  Isolation, sabotage, discrediting, you know - something people typically refer to as the "treatment".  As an example today we have crazy racists and the pronounced matter of our first black President.  A living synonym for change who apparently receives at least 30 death threats a day according to the UK Telegraph.  So much in fact the Secret Service is stretched (but surely coping, so worry not). 

It's bad enough to some of the lowest common denominator elements of the U.S. population who had no problem isolating and torturing blacks in the South even as they increasingly fought for their rights to vote, work decent jobs, and to restore their status as people.  To old school capitalists and outright racists this effective progress had to be sabotaged at all costs.  If you wouldn't join the KKK to harass or kill a black person, your duty was at the very least to be of no assistance to any, save to the extent of offering slave roles in the guise of underemployment.  Even as a white person you couldn't be seen socializing with a black person because you'd be ostracized yourself.  The brutality of this "logical thinking" for a people at the time reaches to modern day impact.  There isn't a black person alive in America, despite how well many have fared, that doesn't live with the weight of this oppression upon them.

But here's the real problem.  Obama in particular is a smart man's man.  Intelligent, charismatic, disciplined - he's exactly the kind of person that could succeed as America's President no matter what color his skin.  His detractors would love it if Obama were the picture of incompetence and foil, for it would forever establish the principle of inferiority of one race under another.  Bigots could live with a non-threatner or a non-changer.  Why, when the world is a cushy place that you're in ruling control of, a non-threatener is the kind of guy you back slap at a house party; not eradicate.  In fact, shoot, why stop at just ineffective?  Maybe a different man would be a step better.  Another black man might even be outright controllable.   Along with stupid and corrupt - a guy like that as President would be a literal jackpot that would vindicate racist policies and world views of "White Power" for another century.  You can certainly bet that if Obama were lousy, merely average, or corrupt, there'd be far less urgency to purge him or to see him "fail".

A dumb Obama, of course, is wishful, dismissive thinking.  The crusty old school loones know that when Obama mantras change, he might actually pull it off.  That's what makes the man the ire of every crackpot with access to a keyboard and able to fire off mindless (and fortunately, largely uncredible) threats.  Unfortunately for the man, that's just how it is.  Effective changers will always be the enemy, the target, and, the justification to be the very worst of what people can be.