Nobody said it would be Al Queda.
You are, of course, correct in that Saddam's regime and the AQ network were as minimally connected as Middle East politics would allow. The one AQ afiliated group and a few mid-level meetings were the absolute minimum sop that Saddam could throw their way in order to make sure that Saddam's own regime was not targeted.
Saddam's support of terrorism was largely financial and mostly directed at the West Bank and Gaza so that he could claim a few "the greater cause" points with those people who'd buy that line of hooey.
If he had decided to provide a bomb to anyone, it would have been Hamas and not AQ. More likely, he'd have kept any nukes for himself to add to his own power -- but might have provided the materials for a "dirty bomb" to Hamas or a Hamas splinter since those byproducts are less traceable to the source than are the refined materials used in true nuclear weapons. Saddam would not have provided a true nuke to strike Israel when Mossad and the US DIA would quickly trace it back to his reactors....he'd have known the response he faced.
However, the other sorts of WMD's -- weaponized anthrax, chemical agents and the like -- would have been easier to provide to surrogates like a Hamas splinter etc. Saddam may well have been willing to do so (though he would have been unable, since his people were only TELLING him they'd kept the programs going in secret without, apparently, actually doing much -- pity we bought the story told to us by defectors trying to win asylum in the USA without getting corroboration).
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