No, but he was financially backed by Islamists. How did some yokel afford the explosives, etc?
He was financially backed by Islamists and the Clinton administration covered it up. The ppl who were going to testify against the FBI were all dead before the testimonies were to take place in court. 2 died in plane crashes and 2 died in car crashes (supposedly). Why Bush didn't investigate this I will never know.
Using your theory, if the Clinton administration did indeed cover up the Islamist backing of the OKC Bombing, then that was the door that the Islamist Terrorists walked in and started planning 9/11.
I'm not going to necessarily discount that Islamic terrorists were involved in anyway with OKC, but I'm suspicious of their involvement mainly because of the relative obscurity of Oklahoma, especially being in the shadow of the bigger animal, Dallas. It is plausible, though.