Racism would be the simple explanation for the reason so many conservatives exhibited visceral hate for President Barack Obama; much of it happening even after his presidency was over. And while racism may be the genesis for their visceral hate, racism is also very easy for racists to deny. Underneath the observant racist behavior, both physical and vocal, lies the real reasons so many white Americans exhibited hate for the black President.
White men especially hate Barack Obama because he brought down the last wall holding up the myth of innate white male supremacy of intelligence, strength, character, morality, and competence. It is the long standing myth that allows a white unemployed, toothless, trailer park inhabitant, and high school drop out male to call an intelligent, Ivy League educated black president, with a JD in Constitutional Law, an "empty suit." .
As a direct result of systemic racism, black American males were denied entry to many areas of performance where they could compete along side and against white men. Consequently, white Americans grew up believing the myth that the worse white man was better than the best black man.
Buoyed by this racist based insanity, much of white America embraced the stupefying corollary to the innate white superiority law that black men didn't have the intelligence nor the ability to play major league baseball, football, and basketball. Whites America also relished the myth that black Americans were incapable of performing the duties required of policemen, firemen, doctors, lawyers, teachers, business men, and politicians.
Though it was a slow process, one by one, each of these myths were destroyed as black men and women excelled in every arena America's white ancestors told their progeny that black men and women were incapable of performing. But white America had one more ace-in-the-hole to support their hold on the white male supremacy myth. And it was repeated ad nauseam. "Yeah, but they can never be president."
The Presidency of the United States was the last barrier supporting the myth of innate white superiority. It was a wall deemed to be higher, wider, and more impenetrable than any glass ceiling that white women, who had similar struggles with white men, faced. When Senator Barack Obama breached the "They can never be president" wall, he destroyed everything their DNA, memories, and racist legends had led them to believe. It created so much cognitive dissonance that it drove some white Americans insane.
Barack Obama's ascension to America's titular throne, The White House, was so devastating that conservative pundits and Republican politicians vehemently hated America so much much that they proclaimed that they "want Obama to fail even if it means America fails". Sadly, never once did they concede that any efforts and obstructions to make "America fail" bordered on acted of sedition and treason.
These acts of obstruction and sedition against the Black President was so ingrained in their psyche that the Conservative Right made unchallenged preferences for America's long time and current foreign enemies in Communist Regimes over the American President. The visceral hate for the Black President was so potent that white Americans who embraced communist leaders did not run the risk of being called a Russki, a Communist, or a Commie; and the rancor those labels in the past had heaped on the recipients of those labels.
The Republican Obstruction to Black President, Barack Obama was immediate and relentless. They opposed and obstructed everything President Barack Obama did, including everything that had been approved or acquiesced to many times over for his white predecessors.
But white America had one more ace-in-the-hole to support the disintegrating myth of innate male superiority. The new mantra buoyed life saving hope for the myth that was barely hanging on life support. "He'll be a one term president", they screamed. "He'll never make a second term".
BOOM! The wall was shattered and brought down again when Obama was elected for his second term as America's President. It was devastating to some white people even more so than the first election. It is alleged that one white man killed his family and then committed suicide rather than face the future of living through another four years of the Black President.
White America apparently need their wall to keep out others they deem inferior from places they have reserved for themselves or for one like them. Perhaps that is why Donald Trump's wall to keep Mexicans out of America was appealing to so many Trump supporters.
White Americans need their heroes. They will even accept Black ones. But for many on the conservative front there is a visceral caveat. Black heroes are acceptable in sports and other areas of entertainment; but only if they are humble or otherwise "stay in their lane", refrain from public gyrations of the pelvic region, and don't use their fame and position to bed pretty, upper class, white women. None of which President Barack Obama violated.
But in America's White House that created another problem for white America. There was a black family in the White House. Worse, for some of them, America had a Black First Lady living in the White House .