Winnie Byanyima: Activists from around the world will defy the terrorists to attend the World Social Forum in Tunis on March 25, determined to make the occasion a beacon for free speech, justice and equality. I am proud to join the leaders of Greenpeace, ActionAid, Civicus and the Association for Women’s Rights in Development (AWID) in highlighting the urgent need to tackle the vested interests of the 1 percent, in order to build a better world for all of humanity.