"It appears that vast stores of weapons will not be found and due to the emphasis put on WMD as justifcation, the policy of pre-emption is pretty much a dead horse. I think we will find a lot of bad things as time goes on but what we find is not likely to match the pre-war rhetoric."

I wouldn't count on it. As long as a country is involved with supporting terrorism, then I think we will still have this "pre-emption" policy. Though it's not *actually* starting a war, but merely responding to a covert attack which is strongly suspected to be coming from a country.
If at same time, this country is openly making threats to other countries, and saying things like it's involved with terrorism, and other hostile acts, then this will have tendency to lower any requirement for any smoking gun type evidence.

"Regardless of future hew and cry over who knew what, when, I suspect there will never again be support for a pre-emptive war without virtually unanimous world-wide agreement. "

I fail to see why having all countries agreeing has any thing to do with it. I think that in the future, the US will have a tendency to depend less on the UN in matters regarding world security- at least until something happens in regards to France and it's obvious hostility towards the idea of the US leading the world. France now, would probably have a tendency to use it's veto power more freely than was previously the case & it seems intent on not having the UN play any significant role in regards to world security.