I think looking at the historical use of race in this country helps to place the current situation of opposition to a President who is of African descent into proper perspective.
I come at this from the assumption that there is nothing biologically significant about the things that we use to categorize people under our racial system. However, in spite of this, we have had and currently have a very real system based on the false idea that there is some connection between a person's ancestry and their behavior.
I put it this way because there is no other way to properly define the racial system in this country. It is not solely about skin color, for example, because there are many persons who are light-skinned, but still black and many dark skinned persons who are not black (e.g. some latinos and persons from India or the Middle East). The same is true for any other physical characteristic you wish to name.
The way in which we have traditionally classified persons along the racial axis is based on the number of ancestors from a particular part of the world a person had. If a person had enough ancestors from Africa, then they were black. In early twentieth century Virginia, for example, the number of ancestors necessary to be classified as black was one. In early nineteenth century Virginia, on the other hand, if more than one out of four of a person's ancestors were from Africa, then the person was black, otherwise they could be white (see Thomas Jefferson's family with Sally Hemmings as an example.)
Today, a person who has some African ancestry has more choice of whether to be black. I have a friend, for example, who is married to a man from the West Indies. They have two children. One of their children has darker skin than the other. One identifies as black and the other as white. I will take a couple of other examples from baseball. Are David Ortiz, Manny Ramirez and Pedro Martinez black or "Dominican" or Latino? How about Alex Rodriguez? How about Derek Jeter?
These questions regarding who is who have always been with us and always will as long as which group one falls into carries consequences with it. And here is where this perspective on the racial system is helpful to understand what is happening now with respect to Barack Obama.
From before the founding of this country up through at least 1865, having a sufficient number of African ancestors to be qualified as "black" or "colored" or "Negro" meant that you were eligible to be reduced to slavery. It also meant that you could not be a citizen in the federal sense, as Dred Scott and his family found out. The apex of this phase of the system came in the 1850's, with at least some Southern slaveholders and their supporters declaring that society needed a permanent group which would form the "mudsill" of society, and slaves were it. Because you needed to be classified as black to be a slave, this meant that blacks were the "mudsill."
After 1865 having enough African ancestry to be qualified as black made you ineligible for public office, higher education, the professions and the highest reaches of success in this country, at least in material terms. In the South, this was mainly a means of preserving as much of the slave system as possible in light of the 13th amendment. In the North, it was simply a continuation of the system, somewhat modified, which had been in existence prior to 1865.
Who benefited from all of this? As usual, it was those who made the rules. In America, the rule-makers were straight males who had European ancestry. This did not mean that all straight males who had European ancestry were destined for great success; only that those were the characteristics which one had to have to be highly successful. This made and continues to make life easier for straight white males because it eliminated the majority of the population as competitors. It is not particularly surprising that the rule-makers made rules which benefited themselves.
In the case of that part of the population with African ancestry, it also created a group which would perform hard labor and menial tasks.
Standing in stark contrast against this system is one line from the Declaration of Independence. Those who have been excluded from power in this country have used that line to force changes in the rules. Those rule-changes, from the abolition of slavery to women's suffrage, to the 15th amendment and the voting rights act and changes to the immigration laws have gradually changed the make-up of those who have become highly successful. Marriage equality and the repeal of the Defense of Marriage Act and Don't Ask, Don't Tell are rules changes which will further expand the pool of persons who may ascend to the ranks of the most successful.
However, the rules have not changed sufficiently to eliminate the old feelings of entitlement among straight white males (primarily), whom the original system, by design, benefited. It is jarring for many, if not most, of this group to see a person who has openly embraced being black holding one of the most coveted positions in American society. A minority of this minority will not accept the rule-changes under any circumstances.
There are a few ways this refusal to accept the consequences of the rule changes expresses itself. Some of it is crude and obvious, like the signs with photo-shopped pictures of the president made to look like a witch doctor, or the open references to his African ancestry or his alleged birth in Kenya.
Other expressions of the desire to return to things as they were are more subtle and flow from the decision of the Republican party circa 1968 to blend an appeal to those who benefited the most from the old system with a desire for national power. The leaders of the Republican party obviously do not like being out of power. In order to return to power, they need some strategy. At present, this appears to be attacking anything which the Democrats do (which also means attacking what a majority of Americans want).
As such, the Republican leaders are taking hold of whatever attacks may work to return them to power. And, since those who are most fearful and resentful of the loss of competitive edge which the rules-changes of the last few generations has caused disproportionately belong to the Republican party, the fact that the President is of African descent and identifies as black is one of the tools those Republican leaders have at their disposal. And so, they will use it.
This leads to curious, if not laughable, results. The prime example, for me, is the controversy over the President's delivery of his "stay in school" speech to grammar school children. Here you have a speech from an excellent role model about the benefits of staying in school. The President's life story is one of a person who was poor, but became very successful because he worked hard to become educated and then put that education to use. The same is true of the First Lady.
However, their stories don't fit the myth which accompanied and justified the original rules giving straight white males a leg up over everyone else. Straight white males are supposed to be on top because they are smarter than everyone else. Women, gays, blacks and other excluded groups are supposed to have some biological defects which justify keeping them as second class citizens. Barack and Michelle Obama are a shock to those who want that myth to be true, and it scares them because it means that if you want to be successful at the highest levels, you will need to be the real deal and you will have to compete with a lot more people than you thought you were going to have to compete with. Many of those who have benefited from the original system don't want to have to be the real deal and would (naturally) prefer to keep the competitive situation less competitive.
Which brings me to Glenn Beck. What a contrast with Barack Obama this guy is. He is relatively uneducated (i.e. high school diploma) and has shown little interest in delving deeply (as opposed to superficially) into even the fundamentals of our form of government. Yet, he claims, without any apparent sense of self-doubt, a position of public influence. He is highly ambitious, but is without any apparent desire to do the work necessary to be a competent leader.
Although persons who are incompetent but ambitious are not the exclusive domain of the straight white male group, I think that the way in which our racial system has benefited that group influences the behavior and thinking of the Glenn Becks of this country. They see someone who, in their mind, doesn't belong in the position he is in and feel resentful and frightened. It doesn't matter that Barack Obama earned his position through hard work and by demonstrating his abilities. It doesn't matter that a majority of their fellow citizens believe that he should be President. He does not "belong" in that position.
The Glenn Becks, Rush Limbaughs and George W. Bush's of this country think that they should not have to become as accomplished as Barack Obama in order to be highly successful. They deserve positions of power and respect just because they say they should have them and (consciously or unconsciously) base that assertion on the fact that they are straight, white males and this is the way it has always been in the "real" America.
There are other themes which are playing themselves out in the opposition to what the President and the Democrats are trying to do. Democracy vs. elitism is one example. But the racial element, being a story as old as this country, has its place and should not be dismissed.