Riots in the arab world

What we are seeing in the arab world is the rise of a society fighting for their freedom, which was silenced for many years...In the 21 st century is no longer acceptable dictatorships as seen in Lybia, egypt or Syria as well...Democracy has become a basic right for the people and they are right to demand that...
The question is: Should the World Powers intervene in these situations or just let things happen like in Ruanda?Nobody want to have blood in the hands, no one want to be blamed for doing nothing while a government kill thousands who was trying to be free, to live better with dignity...the sovereign is changing...everything has its limits...and if we want to live in a peaceful world is time to start acting differently now...we can t intervene in a country based only in selfish objectives as the intervention in Iraq was by the USA, but we can t also let a dictator kill a whole population to keep himself on the power...