It is still too soon to say that we won't find any WMDs, which in all likelihood were either destroyed or very well hidden just before the start of the war -- in both cases, you cannot destroy or hide what you weren't even supposed to have in the first place. It isn't too early to say, however, that we have destroyed the capacity of his government (directly or through terrorists) to use such weapons against us. That's a very good thing.
I am glad our troops were not exposed to WMD, but I realize that it is hard eating crow. I can remember the criticisms of the UN inspectors, Scott Ritter as being guilty of treason, etc. and now they are proven right and the credibility of the United States being destroyed. It is not a pretty sight. You can only holler wolf so many times and expect support when it is needed. This is the tragedy.
It is very easy to dispose of Chemical or Biological weapons and to do it in a hurry. But why wouldn't Sadaam have used them against our troops? If even a few dozen grizzley deaths among our troops from chemical or bio attack were reported by our media it would have had some effect on the home front. Further it would have severely altered the war plans and delayed- for weeks or a couple of months the fall of Baghdad as we are a nation very sensitive to casualties.
And I disagree with you statement above. That is not at all clear. Sadaam had every incentive to give WMD's to terrorist contacts or cutouts once we invaded. We are less secure now than we were before the war in my opinion. Forces that are not a geographic state, that do not rely on terror to ensure loyalty among it's members, and are international (namely AQ) most likely got a good share of WMD's that Sadaam had at one point. This war has not demonstrated that we a safer as a nation even a little bit.