Each autumn, the United Nations General Assembly offers the world's leaders a rare common stage — a moment to speak, to be seen, and to press their people's cause before the international community. This year, Mahmoud Abbas, who leads both the Palestinian Authority and the Palestine Liberation Organization, will not stand on that stage. The US State Department has extended its visa ban on Abbas and other Palestinian officials, barring them from entering the country ahead of next week's session — a quiet diplomatic act that speaks loudly about the current state of relations between Washington a