I accept most of this, including most of the definition of racism. Except that if you read many other articles about racism, other authors include examples such as using the N-word, or, as mentioned in the article, microaggressions such as saying other hurtful things. I believe these fall under the term racism as well, because words can really hurt. Words can be very powerful.
Which is why I take exception when someone who has never met me and knows nothing about me, who has never had a conversation with me, says that I am a racist simply because I am a White man. In today's world, that is one of the most hurtful things you can say to a White person. Yeah, I'm hearing all the "boo hoos" out there. But insulting someone simply because their parents were of a particular race, is racist.
I would love to be in the room when Marley K. tells Barack Obama that he is the son of a racist mother.
Nevertheless, claps for the article.