CAIRO, Egypt — At the five-star JW Marriott hotel on the sandy outskirts of Cairo, where rooms cost between $210 and $600 per night, the lobby was packed. Young staffers in neutral-toned suits rushed busily past Egyptian security officers, and occasionally a person might find themselves nose to nose with Tony Blair or Ban Ki-moon.Some of the most powerful people in the world turned out for the Gaza reconstruction conference over the weekend.All the attendees deemed the event a great success when, by Sunday evening, Norwegian Foreign Minister Børge Brende announced that the nations of the world had raised $5.4 billion to rebuild the Gaza Strip following Israel’s devastating seven-week offensive in July and August.The Palestinian government had asked for $4 billion (despite having earlier estimated the total cost of reconstruction to be over $8 billion), so it was with great fanfare that the higher figure was announced.