Qana massacre

I'm constantly asking myself about the concept of War. It looks like we are still far from the moment when humanity will live without it.
Our modern world gives us much more information about what is going on in our planet. Sometimes is difficult to be in front of the TV news services because of the atrocity that we are able to make all around the planet. But the truth is that more and more people in our planet is witness of the terrible effects of war.
The question here is.. which is the role of the civilians of the world that want to make something to avoid war? what can we do to avoid our political leaders to find a "solution" in war?
From other side the human kind is able to make wonders and inspire. Humans are able to show that culture, freedom, communication, art are pathways to happiness and wellness.
I would like to know opinions of other persons interested into find peaceful actions that civilians of all around the world can perform to express disagreement with war in order to get a real effect to avoid it.

To see some pictures from BBC http://news.bbc.co.uk/2/hi/in_pictures/5228392.stm