Throughout the Muslim world, millions of people have been forced to flee their homes and communities for many reasons: civil wars, interstate conflicts, U.S.-led military campaigns in Iraq and Afghanistan, tsunamis, earthquakes, and a multitude of other disasters. Many have crossed national borders and live in nearby countries as refugees. Many more remain within the borders of their country as internally displaced persons (IDPs). Some are displaced only temporarily and are able to return to their communities when conflicts are resolved or flood waters have receded, but most live many years as refugees or IDPs. For some, displacement has lasted for generations. The statistics are detailed in the appendix to this paper.
This massive dislocation of people affects both national development plans and individual human development. It impacts national security and personal security. It affects relationships between neighboring countries, UN Security Council discussions, and peace processes. In short, understanding— and resolving—displacement is central to development, peace, and security.
I think it's unusual for the chief of staff to go on a trip, particularly on a trip this long. The chief of staff is usually more of a chief operating officer in the White House itself, and normally when your principal—whether it's the president himself or the head of Cabinet agency—goes abroad, you have his deputy and those folks staying behind to help manage operations in his absence.