SOUTH BEND, Ind. - Jimmy Carter came to Notre Dame in 1977. So did Ronald Reagan in 1981 and George W. Bush in 2001.

The University of Notre Dame has a tradition of inviting new presidents to speak at graduation. But this year's selection of President Barack Obama has been met by a barrage of criticism that has left some students fearing their commencement ceremony will turn into a circus.

Many Catholics are angered by Obama's planned appearance at the May 17 ceremony because of his decisions to provide federal funding for embryonic stem cell research and international family planning groups that provide abortions or educate about the procedure.