Given my experience in this forum, I may be cynical, but I lean heavily towards this one in moist cases (newer people in particular).
I'm trying to give people the benefit of the doubt and assume they are simply ostriches or trolls, but given the persistence and vehemence, and really twisted logic, of the denials, I'm starting to lean in that direction more and more.
At the very least, there is an astonishing amount of sheer pig-ignorance of history being displayed by the denialists. More below.
Here's the thing though, the symbol IS NOT RACIST!
The problem with that is that
none of the symbols used by racists, are themselves racist. They're symbols. Symbols have a wide variety of meanings,
depending on context. You cannot explain a symbol in a vacuum, because they don't exist in a vacuum;
Context Is Everything.
"White supremacists using the OK sign is just trolling and not evidence of racism" is about as ignorant as it can get. As is the utterly bizarre "No True White Supremacist" tack being taken by some commentors here.
Let's start off with that, a "white supremacist" is a person who believes in the supremacy of the "white" race (the definition of "white" can vary a bit) over all other ethnic groups. That's what the term means, that is what it has always meant. Insisting that someone cannot be a "true" white supremacist unless they're a member of an officially-recognized organization is the most ludicrous special pleading argument I think I have ever seen here, and it borders on woo, quite frankly.
So, that being established, let's look at the history of this thing.
The OK sign is a long-established and well-known symbolic gesture with a particular meaning. It has been adopted by some white supremacists as a coded signal because of its superficial resemblance to the letters W and P, aka White Power, a very well established white supremacist slogan (I don't think anyone is disputing the validity of that slogan as a white supremacist signal, though if they are, there aren't enough eyeroll emoticons). Its use was originally intended as a hoax, but there are too many examples of white supremacists using it in all seriousness to ascribe all uses to "trolling".
Now, how does this square with the history of white supremacist symbology in history?
I've already posted about the history of the swastika, so just to summarize, the swastika in western European culture had a similar connotation as the OK gesture. It was widely known and used to convey a concept of prosperity and good fortune. For that reason, it was appropriated by one of the most notorious groups of white supremacists in history.
But is that the only example? Far from it. White supremacists have a long history of appropriating symbols and other phenomena for their own use.
Let's look at another well-known symbol, the long, pointed white hood and robes of the Ku Klux Klan. That uniform had a long-established history as an emblem of a certain practice of Roman Catholicism, and is still used as such today in Western Europe (although today it's generally more colourful). It's a symbol of the Holy Inquisition, a Roman Catholic institution dedicated to preserving the purity of doctrine, and rooting out heresy and heterodoxy (sometimes violently, sometimes not). It was appropriated by the KKK in mockery of the RC church, who they considered the enemies of Protestant American culture.
Let's look at the Roman salute, aka the Nazi salute. The Roman salute has a long history, although it's a bit misnamed. It originated in 18th century France in erroneous imitation of what was at the time perceived to be a Roman symbol of honor and allegiance (in fact, it was only documented as having been used by gladiators, "we who are about to die" and so on). It was adopted as an expression of allegiance to a central authority. The Roman salute saw wide use in France, and later in the US, where it was known as the Bellamy salute. The Roman/Bellamy salute was the original gesture made to pledge allegiance to the United States of America. It was adopted by the Nazis explicitly because it was well-known, commonly used, and associated with the authoritarian regime of ancient Rome. It wasn't until World War 2 that the Roman/Bellamy salute was replaced in the US pledge of allegiance with the hand over the heart gesture.
I don't think I need to explain to anyone the appropriation of the Christian symbol of the Cross, an emblem of redemption and sanctification, by the KKK as an emblem of supremacism and terror.
Incidentally, a lesser-known KKK symbol, the cross-and-shield, was also co-opted. It consists of a round shield, or a circle, with an equilateral cross superimposed on it. This is a symbol that goes back to neolithic times, and has had numerous meanings throughout history, and is typically known as the "sun wheel" or "sun cross". Mostly associated with worship of a sun god, it has been used by many religions throughout history. It's commonly used by neo-pagan religions such as Wicca, Celtic Reconstructionism, and Asatru. Various forms of the sun wheel/cross have also been appropriated by numerous white supremacist and fascist organizations, including the aforementioned KKK, and the Nazis; primarily because of its association with Germanic/Celtic paganism.
Which brings up the appropriation of religion by white nationalists. Leaving aside the obvious appropriation of Christianity, the use of pagan/neo-pagan religious symbology and practice by white nationalists has a long and sordid history, going back before the Nazis. The Thule Society was one of the most well-known of these, and its doctrines and symbols were one of the primary influences of Nazi ideology and practice. More recently, many white supremacists have appropriated an altered form of the Scandinavian neo-pagan Asatru religion, much to the horror of its non-white-supremacist practitioners (incidentally, some of my friends are Asatru). They have become so closely associated with the religion that its other adherents have been forced to stop identifying themselves as Asatru, sometimes adopting other names for their religion, to avoid being lumped in with the white supremacists.
To conclude, white nationalists and fascists have
throughout their existence appropriated symbols and practices with denotative and connotative meanings that are well-established (and one would think incompatible) in the wider culture, specifically so that their worldview would be linked to those meanings. In doing so, they provide themselves a more positive image, increasing the likelihood of their being accepted by or integrated into mainstream culture, or allow themselves a mode of
plausible deniability when their racist and fascist worldview is soundly rejected and opposed by mainstream culture ("just trolling, u mad bro?). While the use of the OK gesture as a "white power" symbol may have originally been intended as a joke, it is precisely for that reason it has been appropriated by white supremacists as a coded signal of their worldview. This is not "stupid racists not getting the joke", this is in fact very calculated and well-supported by historical precedent.
As a final aside, trolling using racist terminology and iconography is, itself, an act of racism. There simply is no other reasonable explanation for it. It may not be the same level of racism as setting fire to a cross on someone's front lawn, but it's still racism. Its use says far more about the user than its intended target.