Why did America, and other countries get involved in Libya?

How did any country in history gain their independence? Through war, right? So why are we stepping in and taking over. Shouldn't we let them work it out themselves. I say if the rebels don't have the power to overthrow Gaddafi, then they wouldn't be able to run the country. If the war is fought by the US and other nations then the people of Libya will have no pride in their country, and rely on us to keep helping.