C'mon lads...yous don't seriously believe BJ is actually writing "stupid because he was a coon" without any kind of context?
In his book, the coon in question is a character called Dean. According to a NY Times review, Dean is "the most sympathetic character in the book". So when there's a passage like:
"Dean shrank before him, and the ambiguities in his status seemed to fade away. There it was, en clair, decoded. He was a coon, and he was stupid, and he was stupid because he was a coon. "
It's clearly implying the world of this book is a racist one, which Dean tried to hide with ambiguity, but once that wore off, he was confronted with racism and its victim's inherent feelings of self-doubt. The character of Dean is a terrorist from the Midlands, albeit drawn sympathetically. I expect the author's intentions are to show what can happen to a put-upon minority.
If anything, it seems quite a liberal work. Upon release in 2004, it didn't cause controversy as obviously people read it as intended.