Because even without support the Aussies would've gotten that trade agreement.
Turkey was going to get military assistance at least...and money guarantees most likely...simply due to geography...the US is pushing NATO to offer this support...to the point of nearly destroying the organization...or did you miss that little piece of the news.
And, as Box pointed out (by repeating what I have stated in other places) France, Germany, Russia and China financially benefit from the status quo...simply because they've been continuously violating the commercial rules they agreed to. France contracted with Hussein for control of Iraqi oil, Germany has been supplying chemicals to Iraq that along with valid uses can also be used to build WMD...etc...
Its >convenient< for the French to say "our people don't support action"...since they know their inaction will mean billions in revenue.
And I suppose you're bringing up Soviet war attrocities as some point about the US dividing the "spoils" of Iraq as incentive or some such nonsense. I wasn't a history major...but I do know a bit about it.