The people who rioted inside and outside of the DNC convention in 1968 (and those like Bill Ayers, who rioted a year AFTER the 1968 convention) are now the core BASE of the Democrat Party.
This is not like anything we have seen before. These are people who've loathed America for 40+ years.
They do not have the American Way or the Constitution at heart. When Obama says that we cannot live high on the hog anymore because others in the world don't have it so well off, I have to disagree. Disagreement means debate and counter argument. It doesn't mean anything violent.
As Ann Coulter pointed out to Harry Smith, it isn't the "Right" that gets violent much. It is very much the exception to the rule. Being on side of law and order and all that. Our president have been killed by democrats, communists, liberals, actors, and Reagan was targeted by someone who seems to have been clinically insane.
Or if you don't like a Biblical explanation, just forget about it because it's a done deal for the next 4 years.:)