It's one of the most polarizing and emotional issues of our time. In a nation divided over questions of morality, religion, and life and death, the abortion debate rages on.

Despite the risks inherent in his taking on such a sensitive issue, President Obama continues to bring the right tone to the debate.

Consistent with his campaign messages, he urges respectful, good-faith discussion. His controversial commencement speech this week at the University of Notre Dame offered the latest opportunity to seek common ground.

Dozens of American Catholic bishops criticized Notre Dame President the Rev. John Jenkins for inviting the president and giving him an honorary degree because he supports abortion rights. More than 360,000 people signed a petition asking that the invitation be withdrawn.

But that would not have respected the office of the president or moved the nation any closer to a resolution. Nor would denying the president the podium have done anything to further the values that colleges and universities hold dear, such as free speech and informed, critical thinking.

Jenkins deserves credit for standing up to powerful forces within the church and honoring the invitation. Archbishop John Nienstedt of the Archdiocese of St. Paul and Minneapolis was one of more than 70 Catholic bishops who publicly objected to the presidential appearance. Jenkins defended the decision by calling on his college community to appeal to both "faith and reason" and to "foster dialog with all people of good will."

And the president should be commended for displaying calm under fire. Obama accepted the invitation knowing that the church and university disagree with his abortion rights philosophy. He respectfully handled several interruptions in his speech by anti-abortion protesters by waiting patiently until pro-Obama chants quieted the protests. His presence and message demonstrated his respect for all Americans, whether they agree with him or not.

This week, the Vatican newspaper said Obama's speech confirmed that signing the Freedom of Choice Act is not his highest legislative priority. The Vatican article didn't mention the U.S. bishops' protest; it simply quoted Obama as inviting Americans to work together to reduce the number of abortions and unwanted pregnancies.

Even so, the true test will come when the president is faced with proposing, approving or rejecting legislation that might further inflame the issue.

For now, Obama's approach is reasonable. He's helped build a foundation for a more informed national discussion. Given the moral and often religious implications, it is essential to continue talking, to disagree without being disagreeable, and to join forces to find that elusive common ground.