On the issue of racism and from what I hear over a long time but even daily, I don't think most Caucasians truly understand it themselves.
 
It can be very subtle.
 
I grew up in a home where I constantly heard parents or others remark that they weren't prejudiced.  
 
I grew up in a neighborhood that was mostly white, attending a parochial high-school that was on the edge of the Barrio with a greater mix of Latinos and only 2 blacks out of 500.  The de-facto segregated black part of town, known as the East-Side, was outside my experience.
 
In my last high-school years, we would drive over to the East-Side's busiest liquor store, and look for "some old black guy" to buy us booze.  Eventually, we developed a regular relationship with one for that purpose.  And as I look back on those days, it almost makes me sick.
 
In 1971, two policemen were gunned down in my city during a time when folks in this county were all panicky about the Black Panthers and other developments in the news.  The police and prosecutors were desperate to reach closure.  They rounded up three black men who had never met each other before their arraignment.  
 
It turned out that I knew one of them -- a poor 19-year-old black kid from Alabama who had come west to find a better life for his mother and siblings.  There was no way, given our limited association, that he could've done such a thing.  But the papers published news about the arrests and three successive trials in such a way that someone from my realm of experience would easily assume they were all guilty.  And -- I did. 
 
In other words, they had to be guilty because, after all -- they were black.
 
They were all eventually acquitted and let go.  Their lives were destroyed.  And to this day, when bringing up memorial reminiscence of the two policemen in the newspapers, there are always comments by retired cops who insisted the three were guilty.  There has never been an acknowledgement that they were railroaded.  They were "not guilty" but unacknowledged to be innocent.  A star reporter on the local paper had written a book about it -- son of the Washington Post Ben Bradley.  The facts, the evidence never-explored or suppressed, testimonies of both black and white -- all revealed in his book.  There is no chance that he was in error about the Truth of it.
 
There's another phenomenon, too.   A Caucasian chooses to work for a black genius, knowing he can learn something.  A change in political regime occurs.  You don't hear anyone say anything; people are polite outwardly.  And the thought simply doesn't enter one's mind:  "things have changed; the days of bigotry are gone" he might think.  One almost has a delayed reaction:  looking back to insinuations, the look in the eyes of other whites.  And then it dawns on you.
 
People with even tincture of racist attitudes often don't share it, and they don't admit it to themselves:  "Some of my best friends . . " yada-yada-yada..  Even overtly racist groups seem to hide themselves -- by wearing white sheets at their gatherings.  
 
Go in peace.  End of sermon.