Earlier quoted context omitted.
That doesn't necessarily rule out al qaeda involvement, there have been caucasian taliban et al before. But we shouldn't jump to conclusions until we have the facts regardless.
I remember the Oklahoma bombing and the first picture was of some random brown muslim guy. Turns out, it was a white athiest. Look up the FBI stats on radical muslim bombings on US soil vs radical christian vs radical athiest bombings. In fact, I seem to recall that radical jews had more attacks on US soil than radical muslims. And since 9/11 was so neatly sown up, we'll never really know who was truly behind it.
Link: http://en.wikipedia.org/wiki/Timothy_McVeigh#Political_views...