This is only common sense.
And thanks for clarifying the intended meaning of your post. IMO, your expectation that the bulk of Saddam's weaponry should be easy to locate has caused you to over-generalize from the available information.
You may well prove correct in that view. I think my main point of disagreement with others rests on the basis that I do think this evidence should prove easy to locate. At least, that is, easy to locate now that we've occupied Iraq & removed the Ba'athist regime. If I am eventually proven wrong on that particular point, then it's conceivable I will be proven comprehensively wrong in my conclusions.