Today marks the International Day of United Nations Peacekeepers.It is time to pay tribute to those who devote their lives to world peace.Since the first UN peacekeeping mission in 1948, more than 3000 military, police and civilian personnel have lost their lives in the service of peace.Today, some 125,000 women and men serve in 16 peacekeeping missions across the globe.Yet the world now is far from being peaceful.The Middle East and North Africa are chaotic.Even in Europe, Ukraine is in a crisis.The demand for UN peacekeepers is ever increasing.So how does UN peacekeeping respond to the new world situation?And is today's peacekeeping more of a political process or military challenge?