It is great that you are strong enough to support a friend regardless of whether it is the unpopular view. As you suggest, I think Britain and eventually the rest of America's friends will come around to support America's views - Denmark and the Netherlands already have. (OK - so the Danish navy hasn't won a battle since ?forever?, its the moral support that counts.)
What is truly bothersome to Americans is that some support the continuing criminal regime of Saddam - its completely unfathomable to me. Anyone that suggests that refusing weapons inspectors is no justification for military action is a Saddam supporter.
Its like the lessons of history have never been learned. Furthermore, hiding behind 'international law' or suggesting UN approval is required is plainly disingenuous. People who suggest this don't care about international law in and of itself, they use it as a tool to promote or reject agendas they seek for other, most likely economic, reasons. The people who say that the UN should decide whether or not Iraq should be invaded are simply people who don't want Iraq invaded - they have no respect for the UN or concern about the Iraqi people, they will just suggest whatever they can to avoid toppling Saddam.
Their lack of respect for the UN is proven by the fact that they have no problem with Saddam violating UN resolutions and breaking international law. Because it seems sure that the UN Security Council would veto an invasion - they say the UN must be consulted; however, if the UN were sure to advocate invasion, these same people would be telling us that the UN is worthless and irrelevant. They seek to use the UN in yet another attempt in their never ending quest to have some non-American control over US policy.
Finally, no modern American president has taken the country to war without a very clear smoking gun. The country would not stand for it. I can't say for sure, but I feel that the UK is probably the same way. In this light, I am sure Bush and Blair will reveal a damning package of evidence against Saddam when the time is right for their many political/international/personal agendas. Blair knows that committing Britain to America's side would be a disaster politically if the evidence is weak - thus we have to assume that the evidence is strong.
After all the arguing, it really doesn't matter - we're just talking political niceties at this point. The US could invade Iraq, establish a democracy and leave it at that and the whole world would just forget about it or pretend they wanted Saddam out all along. I'm afraid the arguments of many on this thread have brought me over to the side that believes it really doesn't matter what the rest of the world thinks - unless one is willing and able to act on their words, their words are irrelevant.
This will end - and Saddam will either allow full inspection access or will be out of power. That's all there is to it and everyone is free to pick the side they are and will be on, I'm sure the UK will chose correctly.