Larison explains why Obama is described as far left and Bush was described as far right:
The impulse to label an opponent as an extremist is a common and tempting one. It is a very easy thing to do, provided that you are not concerned with accuracy or persuading undecided and unaffiliated people that you are right. These labels are not descriptive. They are a way to express the extent of one’s discontent and disaffection with the other side in a debate.
When some Republican says that Obama and his party have been governing from “the left,” he might even believe it inasmuch as Obama and his party are to his left politically, but what he really means is that he strongly disapproves of how Obama and his party have been governing. He may or may not have a coherent reason for this disapproval, but declaring it to be leftist or radical leftist conveys the depth of his displeasure. That is, it is not analysis of political reality. It is therapy for the person making the statement.
The same thing goes for progressives who were trying to find words to express how outraged they were by Bush. Inevitably, many resorted to using labels such as theocrat, extreme right, radical right and the like. These did not correctly describe the content of Bush’s politics, but they did express the critics’ feelings of disgust and loathing for Bush’s politics.
The Dish 