After all, Hussein killed millions of his own people.

Could it be because one President is Obama and the other was Bush?

There is a tsunami forming in the middle east that began  when the people of Tunisia rose up and threw off the bonds of a dictator in order to govern themselves. If America stands for anything at all  it is the right of a people to govern themselves so when a people tries to topple a dictator we need to stand up and cheer. In Tunisia and Egypt we ( and the world)  were lucky that the dictators chose to run and did not engage in wholesale slaughter of their own people because they could have done just that and that would have put a quick end to these upstart rebellions.

Then Libya tried to follow suit and we had a choice to just stand by and try the usual ineffective diplomacy crap and let Quaddaffi put down his rebellion as he brutally told us he would do or to act. The UN got off their duffs and acted and even the Arab league gave us (the west) the go ahead. End of story. To not act would have been unconscionable in the same way that Europe did not cover itself in glory when they sat around for two years and let the killing go on in the former Yugoslavia because "things might get messy".

The question to be asked is not why we didn't and/or don't act to defend the downtrodden in every situation but what we should do in each individual country.  And trying to bolster the rebels in Libya was the right thing to do both from a humanitarian stand and because in the long run we want more countries in the middle east(Saudi Arabia?) to follow the example of Tunisia and Egypt. Quaddafi winning would have stopped this awakening and nipped it all in the bud. Not in Egypt or Tunisia but anywhere else the people were fed up. No matter what happens now in Libya we at least stood for principle and tried to help a people throw off a cruel dictator.

The US can't turn a country into a democracy which is why I objected so strongly to the invasion of Iraq and think that war was completely wrong (  I believe I differ from BTD in this because I thought he  supported that war). But when the people of a country rise up we have an obligation, no a duty to speak up and support them.  Sometimes that will mean just condemnation or sanctions but on rare occasions it will mean sending in the military to help in small ways. If the US or the west invaded Libya and did the fighting for the people that would be the wrong way to proceed as well. The best we can ever hope for is to level the playing field as much as possible.

"The lead role the United States is playing in the military action against Libya threatens to scramble an emerging consensus over the need to trim defense" spending. "It is just plain vanilla that it will make it harder to cut defense in the near term," said Republican economist Douglas Holtz-Eakin. link

Once you go in for obvious humanitarian reason you can bet that the temptation to go further will be there. I pretty sure to go further than humanitarian was by designed.   To succeed you got  to continue the bombing of tanks and troops to get Gaddafi or make he run out of Libya

The main reason Obama says we are not there for  regime change is because that is very unpopular to say after Iraq.  He does not want a Bush II copy on his decision in Libya.   But I bet you dollars to donuts that in the secret war room before the first strikes started in Libya  Obama has told his generals take out Gaddafi.  I don't care how you do it but remember I never told you to do it.  

Remember Thomas Beckett when the King Henry said

"Will no one rid me of this meddlesome priest"

Sometimes countries need to figure these things out w/o the sanctimony and the obese military of a country that spends freely killing people all over the world while simultaneously tightening it's belt in regards to it's own citizens.

And as far as the Obama Doctrine, what a joke, as pointed out several times above, the humanitarian aspect only applies to nations who have something we want.  Never mind that the US has never been successful in helping regime changes, if anything, this is era we will be talking about in 20 years when that region becomes another problem child, hostil to the overbearing US.

Personally, I think such "humanitarian" missions need to be done on a private volunteer basis and not involve the US military at all, if at all...like the Abraham Lincoln Brigades who volunteered to fight facism in Europe.  If the atrocity in Libya, Ivory Coast, Syria or anywhere else troubles you deeply, no one is stopping you from catching a flight to join the rebels in any nation...just don't send somebody elses kid who may not be willing to sacrifice for Libyan liberty, or pick you troubled nation.