Despite the moronic accusations that come our way about our "world policeman" identity, we are no where near such a thing. Our first concern is to ourselves then others. Often, a humanitarian issue is in our interests. Often it is not. We have to be able to point out that foriegn people have to accept that they have do for themseleves before we "intervene."
As far as Darfur, nations like France and China have business to do, which means the UN will never do anything of substance with nay votes coming from the Security Council. It was Bush and Blair that pressured and pushed the UN to even look towards Darfur. And in the end, no one in Europe decided to lead a mission and the UN even dismissed the International Court's decision to bring Bashir up on charges against hunmanity.
The "right" thing is often a contradictory thing anyway. Today, morality is decided by international law. "Right and wrong" comes down to whether or not the decrepit of the earth can get the UN to legitimize their turned backs. It's also decided in accordance to location. Notice how a UN declared "illegal" act over Kosovo met with minimal criticism from Europeans, but a UN declared "illegal" act over Iraq met with extreme hatred and criticism from the same people? The only consistent is American action to do what is "right" despite the twisted criticisms and pathetic focuses on ulterior motive accusations from those who like to think they are our voice of conscience and morality.
Helping Haitians is the "right" thing for two reasons. One, they are suffering and two their suffering will float to Florida. Before long, the critics of the world will focus on the second reason alone. And if the UN wasn't involved and Europe turned its back, we would be criticized for our "intervention" as we were in 1993 and 1994, when people like me were deployed into Haiti to deal with their coup.
"Right and wrong." As long as we keep deciding for the most part what this means, the world will be heading in the correct direction. God help the earth's population across the oceans if we ever take a UN or European attitude about it.