I'm too lazy to go looking for the transcript of the interview Al Jazeera did with the two Al Qaeda leaders in June which they broadcasted a few days ago, but I believe Ramzi bin al-Shibh and Khalid Shaikh Mohamed said Al Qaeda did think about hitting nuclear plants but then decided things might "get out of hand" if they did that. So I guess you are sort of right if that interview is indeed authentic. Even so, how stupid were these guys? Any sane person could tell Plan B would cause things to get out of hand also. But then again, fundamentalist Islamic fascists who belive they'll go to heaven after murdering thousands of "infidels" probably shouldn't be considered well-adjusted.
You should look into what bin Laden was telling his followers before 9-11. Defeating the Red Army in Afghanistan and bringing down the Soviet Union, he said, had been the hard part. The easy part - the destruction of the United States of America - was still to come. That task would be easy because America was corrupt and cowardly and rotten. It would not fight (as the debacle in Somalia had shown); it was a slave of the Jewish conspiracy; it cared only for comfort and materialism. Al Qaeda probably has changed its opinions somewhat since, but in the interview the two leaders said they were ecstatic over how effective the attacks were. But then again, maybe they were bluffing. Name a good book on bin Laden and Al Qaeda that you've read and I'll go check it out.
Peter