What can you accomplish in a day?
A friend asked: "Why [are we] concentrating on Iraq, when there are still so many humanitarian tragedies around the world? "
Because there is only so much that can be accomplished and the United States is not omnipotent, omniscient, nor, as you show, supplied with endless will. We know about Iraq because we have studied it well and learned from fighting it before, our lessons from fighting in North Korea are no longer fresh or relevant. We have 17 UN Security Council Resolutions allowing us to act in Iraq, unlike Zimbabwe where we have no specific authorization. Iraq is the closest thing to a moderate Islamic nation that is available for molding into a democratic state after an invasion, unlike Iran which is a very different state. Specifically, Iraq has a brittle shell of dictatorship that can be readily broken; Iran is much more organicly empowered and has the capability of achieving its own liberation.
These are truths about the world that are not provided by our government. Iraq is a target of opportunity that is being acted upon for more than one reason. The problem with a truly "international" effort is that most other governments are so corrupt as to make the US look pure as the driven snow by comparison. Make no mistake, we have bad people in the US government, corrupt people in the US government, and stupid people in the US government. That is just the State Department. Compared to most of the rest of the world, we are as saints. If you doubt this, look at the "international" leaders, the French, and how they conducted themselves in Algeria or how they responded to Greenpeace or what they are doing in the Ivory Coast right now. While an "international" effort looks clean from a distance, I assure you that it is very sordid in detail. "International" solutions are only effective when the lowest of common denominators are appeased and have their palms greased. Would you want to have your people associated with a movement that satisfies the power lust of Syria and the politics of Chirac?
France is dependant on illegal sales of material to Iraq and makes us look like saints. Germany accuses our president of being like Hitler and then stops our meaningful action against openly fascist Iraq. That makes us look like saints. Brussels Defense Minister announces that the purpose of his military is to maintain a high standard of living for their unionized personnel, not actually do anything so gauche as to be able to project military force in compliance with their treaty obligations. That makes us look like saints. Zimbabwe is run by a bloody handed dictator who is systematically starving his political opposition by the millions, which makes us look like saints.
You should go rent the DVD of "Lawrence of Arabia" just because it is a fantastic movie and also because it really makes some effort to look at the brutal aspects of foreign policy.
I am not saying that the US forces or the US government or the US leadership ARE saints. In comparison to the effect of the actions of a jaded, crappy international community, the effect of our actions are saintly or at least have the prospect of becoming saintly.
If you wait for a perfectly pure sequence or actions, you will continuously miss the real moment where some good can be done. If you wait for a moment where everybody in the world agrees that some action must be taken and for that action to be utterly pure in motive and behavior, your grandchildren will have grown old and died of despair. We do the best we can with the situations we are in and the tools we have available. If you want to ask more than that, get on your knees and pray. In the meantime, let the flawed humans do their best and support them if you possibly can.