On behalf of all the men and women of the Department of Defense, I extend my deepest condolences to the family of Abdul-Rahman Kassig, also known to us as Peter, who time and again volunteered his service during times of war -- first as an Army Ranger in Iraq, and later as a devoted humanitarian, providing aid to victims of the conflict in Syria. Like his fellow veterans of the 9/11 generation, his strong desire to continue making a difference in the world after serving in uniform -- to continue leading a life of purpose -- is an inspiration to us all. His brutal murder is one more reminder of the Islamic State of Iraq and the Levant's (ISIL) ruthless barbarity; there is no starker contrast between the inhumanity of ISIL and the bright and generous spirit of the young man they murdered. As we join his loved ones in mourning his loss, we also celebrate his service, and we celebrate his commitment -- a lifetime commitment to, as he said, "stand beside those who might need a helping hand."