Ill agree that Obama exhibits traits of the effect on certain issues, such as his handling of the economy. I was shocked at his response when asked how he graded himself and he said "a solid B+". Whether you think Obama is right or wrong on the issues, his inability to communicate his agenda alone is "C-". Reality check time Barack.
His detractors (meaning: the nuttier end), do not suffer Dunning-Krugar because the condition actually requires for the victim the ability to actually think. They don't think they just spew whatever nastiness their small-minded head can compute, from his birth certificate, to him being a Muslim, to him being a Socialist/Communist/Nazi (yes I know it doesnt make any sense) to finally accusing him of being the Antichrist.
But the most egregious example of the denial of reality was from the Bush Administration. Who actually had the gall to proclaim "Mission Accomplished" 9 years before the war actually ended.
Journalist: "Have you ever made a mistake"?
Bush: (Long Silence) "Nope, cannot think of a single one".
It finally took comedian Stephen Colbert to get the message through to him.