1960: DAY OF DRAMA AT UNITED NATIONS A sequence of dramatic events at the United Nations, beginning when Nikita Khrushechev takes the speaker's stand for the third time to repeat his demands for the admission of Red China, drastic reorganization of the U.N., and the removal of Dag Hammarskjold as Secretary-General. King Hussein of Jordan, speaking as the head of a small nation that has experienced imperialism, denounces Red attempts to wreck the U.N., and terms the new Soviet imperialism the most brutal the world has known.   India's Nehru defends the present structure of the world organization, and makes a characteristically eloquent plea for peace.  Finally, Dag Hammarskjold speaks in his own defense and defies Mr. K's threats, receiving a standing ovation from the General assembly.