A friend shared an article on FB from the Huffington Post - the quote below is from part of the article, the rest you will find by clicking on the link 

"Celebrating" the killing of any member of our species--for example, by chanting USA! USA! and singing The Star Spangled Banner outside the White House or jubilantly demonstrating in the streets--is a violation of human dignity. Regardless of the perceived degree of "good" or "evil" in any of us, we are all, each of us, human. To celebrate the killing of a life, any life, is a failure to honor life's inherent sanctity.

Plenty of people will argue that Osama Bin Laden did not respect the sanctity of others' lives. To that I would ask, "What relevance does that have to our own actions?" One aspect of being human is our ability to choose our own behavior;  more specifically, our capacity to return good for evil, love for hate, dignity for indignity. While Osama Bin Laden was widely considered to be the personification of evil, he was nonetheless a human being. A more peaceable response to his killing would be to mourn the many tragedies that led up to his violent death and the thousands of violent deaths that occurred in the attempt to eliminate him from the face of the Earth; and to feel compassion for anyone who, because of their role in the military or government, American or otherwise, has had to play a role in killing another. This kind of compassion can be cultivated, as practitioners of many different spiritual traditions and humanistic philosophies will attest.

Article from here The Psychology of Revenge: Why We Should Stop Celebrating Osama Bin Laden's Death