After 9/11, new atheists writers criticized all the religions of the world especially Islam. They linked world's major conflicts and terrorists' attacks with religions. Their objective is to defame religion and through this way weaken the belief of masses on the existence of God. Moreover, they want to promote atheist ideology across the world and eradicate the role of religion in all sphere of human life. This study is an historical analysis about the common objection of new atheists that religion is the primary cause of wars and conflicts. This is qualitative research in which data is gathered through secondary sources; books, articles and online sources. The study finds that religion is not primary cause of wars and conflicts across the world. There are other economic and political factors and motives behind the wars, which are neglected by new atheists. Moreover, study explore that religion promotes peace and harmony, atheist overlook this role of religion and emphasize only to attach religion with violence and anarchy. Islam prohibits the killings of innocent people and directs to save the lives of humanity. Muslim rulers have been treating with respect and dignity with non-Muslims in their regimes. Religion is necessary part of human life, and it develop individual as well as society with strong moral values. History shows that atheist regimes of the 20th century caused more bloodshed than the rest of the nineteen century. Stalin, Tito, Mao Zedong, and Pol Pot are responsible for millions of murders. Blaming religion as the sole cause of violence in the world is illogical and irrational.