Nicky Campbell presents a special edition of The Big Questions, asking whether war can ever be just. Amongst those taking part are historians Tom Holland and Margaret MacMillan, Major General Tim Cross, author and former army chaplain Dr Peter Lee, Guardian columnist Seumas Milne, Bruce Kent from the Movement for the Abolition of War, Dr Usama Hasan from the Quilliam Foundation, and the philosopher Dr Helen Frowe. Show less