The following comes from Zochrot, an Israeli organization dedicated to commemorating the Nakba, from www.nakbainhebrew.org:
In the Zionist collective memory, Palestine of 1948 was 'a land without a people, for a people without a land.' Yet, the place where Israel was founded was never empty. This was home to almost one million Palestinians living in over 700 villages and cities, most of which were depopulated and renamed in the period during and immediately following 1948. The Palestinians who were expelled during the Nakba have since grown to become the largest refugee population in the world. In addition, within Israel a quarter of a million Palestinians live as 'internally dispaced' refugees - citizens in their country but defined by law as 'absentees,' denied the right to their land, homes and property.
The Nakba is the central, unspoken trauma at the core of the Israel/Palestine conflict. Bringing the Nakba to light, and undoing its ongoing injustice, is essential to achieving reconciliation between all the peoples of this land.