This question sounds like a philosophical question, and for many years it has been.

As a result, discussions about peace lean toward idealism or theory, and the idea that this question can be answered with modern social science has not been a part of the mainstream discussion.

The history of humanity can be told as a history of war. From the classical age through the dark ages and into the middle ages, the renaissance, and modern history, warfare has always been a part of Human history.

The international system is determined first and foremost by power – particularly military power – and as a result, war is a fundamental part of the international system.

Activists would say that war is a conscious choice of politicians, and if decision makers were to reject military force as a tool of public policy then war would end.

War is clearly affected by social institutions and structures and the World has been trending slowly and steadily in the direction of peace. 

If these trends are supported and extended, peace is possible

Economic development, Human development, and global peacekeeping systems have all manifestly contributed to peace. 

If these systems are strengthened, there is every reason to believe that the World may continue to trend towards peace.

There is a developing Awareness that peace is possible.