In a sun-lit office in the Yarmouk Palestinian refugee camp near Damascus, Hamas leader Moussa Abu Marzouk looks at home. But he is a new resident of Syria, having arrived just three years ago after being expelled from Jordan.
In 1997, he was deported from the U.S. after being held as a suspected terrorist for two years. After being largely sidelined by the Oslo peace process, Hamas is now back at center stage in the Israeli-Palestinian conflict. Western governments, Israel and many Palestinians believe the group represents a major threat to regional...