Racism as a mental illness: Is America suffering from PTSD?

With the rise of Donald Trump, the Mosque murders in Quebec City and the Conservative Party leadership race (Canada) in full swing, racism is rapidly becoming a popular topic of discussion.

I came across this video this morning on YouTube that argues racism is a mental illness and that the US is suffering from PTSD as a result of centuries of racism. 

I have never heard of racism being considered a mental illness but it makes sense. A lot of the behaviour that goes along with racism, like anger and hate for example, are not considered 'normal' behaviour. And, apparently, according to this video by 'This Matters', the US government acknowledged racism is a mental illness many years ago. 

What do you think? Is racism a mental illness? Should people who engage in racism be treated for PTSD? Or should we clamp down on people who spread hate and throw away the key? 

Please share your thoughts on this hotly debated topic in the comments below.