Princeton University president Shirley M. Tilghman, left, stands near as United Nations Secretary General Ban Ki-moon waves after speaking to students and faculty Friday, April 17, 2009, in Princeton, N.J. In his speech, Ban called 2009 a "make-or-break year" for the world. With growing poverty, financial risks and complex national security problems across the world, it's more important than ever for nations to work together, he said.