Well, he could do that, too. But the control issues are the same. There has to be a hand-off of control and, ideally, that hand-off has to occur even if Saddam is killed. So there is really no important difference between the two scenarios, except that in one case we get whacked immediately, and in other case we get whacked later (maybe). And, from GWB's standpoint, the calculation is exactly the same. In fact, it's exactly the same even if, in reality, Saddam's bluffing -- even if he has no capability to manufacture powdered anthrax in anything but gramme quantities. We have to assume the worst, because the worst is perfectly plausible.
Control-freak Saddam is not going to let any of those germs leave the country
until he knows for sure he is done for.
There are no sleepers now in the USA waiting for secret codes to be sent.