Not only am I against it, I greatly dislike the term itself, which I feel helps to foster the very thing that it rallies against. There is only one human race. One. No more. By saying that someone is racist, you are tacitly acknowledging that there is more than one human race, thus furthering the idea that there are large differences between people of differing ethnic backgrounds.
Biologically, there are almost no differences between any two people in the world of the same sex, and those few that do exist are entirely superficial. As a species, there are no differences between any two peoples in the world at all. Say it with me: There is no such thing as race within the human species. Most differences that exist are cultural in nature and have nothing to do with biology, appearance or what is commonly referred to as ‘race’.
Sadly, many people are prejudiced against people who are superficially different, or who come from a different culture. Unfortunately, these are judgements made in ignorance which can only be corrected if people are willing to be educated. A proscriptive attitude that ‘racism’ is unacceptable will only take us so far. The next step is to foster the knowledge that races do not exist, leaving even less footing for prejudicial attitudes.
In short, if you agree that there is only the one human race, stop using the terms racist or racism. The attitude can be far more accurately described as prejudice, discrimination, narrow-mindedness or ethnically biased. There are many other terms as well (see your thesaurus), and I don’t really have a problem with ‘ignorant knucklehead’ either, but trying to counter an misguided attitude by using terminology that lends credence to it seems counter-productive.
As an interesting side note related to fear as the cause of this particular brand of prejudice, see this article: