Not quite dumb enough to be a suicide bomber, but close. 
FQ13
PS I don't want to sound unfair to muslims. Mcveigh was pulled over with a gun in his lap. He didn't shoot the cop and drive off. Why? Did he think it might get him in more trouble than the dozens of counts of murder? It must be something in the fertilizer fumes that causes brain damage.
Or it's possible that like
he said in interviews, He did not know they had gotten a description of his car, he did not know they would connect him to it.