I don't think that the issue with the international community is about trustworthiness, but rather about their motivations. All of the major European countries deal with countries like Iraq, Iran, Libya, Syria, etc., because they are a major source of trade dollars. Also, most European countries rely on Middle Eastern countries for almost all of their oil (unlike the US who's about 50% or so.) So these countries can't really be seen to be going against their customers or suppliers without risking severe damage to their economies. Think of the US declaring war on Canada, Japan, and Mexico. Plus, these countries all have contracts with the existing regime that would be in jeopardy if new people we put into power.
The second issue is terrorism. Most of the major European countries have paid bribes to terrorists to leave them alone at one time or another, and this is their preferred method of dealing with the problem. They feel it's better to pay the bully than to stand up to him. If that's their thing fine, but it makes it hard for them to do anything that might tick off the bully again.
Lastly, I agree with those who say that countries like most of those in the Middle East aren't looking forward to a democracy being installed in Iraq as it will make them look worse than they already do. Democracy tends to spread quickly, and once it does the ruling monarchs and their dynasties aren't going to survive for long.
If you look through post-WWII history, very few countries have done much to help other countries except for the US and the Soviet Union. Europe, the Middle East, and Japan have been little more than money sponges since 1945. As a result the economies of all these countries are very fragile and it doesn't take much to seriously disrupt them. Yeah, they'll all be against us in the beginning, but once Sadam is gone we'll have no problem finding all kinds of fair-weather buddies who were behind us all the way.