Four decades ago, a gathering of world leaders here was a security nightmare. Cuban leader Fidel Castro stalked out of the Hotel Shelburne and threatened to sleep outdoors because his entourage couldn&#039t pluck and cook chickens in their rooms. Soviet Premier Nikita S. Khrushchev banged his shoe on the table at the United Nations, stirring passions. And the presence of both men brought anti-Communist demonstrators into the streets. Full Story