There's no doubt the oil had a role to play in invading Iraq. But it's a minor reason. I don't think I could name one single oil-using country who isn't interested in a stabile oil market. But making it the one and only reason, which a lot have, is wrong.
Yes, USA lead the war against Iraq. They are the superior force in this coalition. But other peace-loving, not so greedy nations have joined as well. Britain, Denmark, Poland, Italy, Spain etc. The biggest problem is that Bush had a good plan to win the war but none to win the peace. The most unstabile areas in Iraq is controlled by US forces. That doesn't neccesarily mean that US forces are bad, it also has something to do with which area we're talking about. Let's have that in mind.
I will repeat what I said when I created this thread. Saddam didn't obey (sorry about the choice of words, don't really know what word to use - you know what I mean) the UN after having been threatened with war. If we just had let him shit on our threats everyone we threat will do the same, because we won't react to it anyhow.
Finally, no respect for those countries who declare themselves against the war only to be caught in having great deals with Iraq.