The success of a great human migration depends on many individual pieces falling into place. There must be discontent with an unpleasant, perhaps even intolerable status quo. There must be idealism to drive the movement, a powerful vision of a better life beyond the horizon. There must be great courage in the face of terrible odds. But most of all, every migration needs its leader, the indispensable charismatic figure whom even terrified men and women will follow headlong into the abyss.
