Nuclear weapons ushered in a period of peace never before seen in human history. Death rates in war have been at historic lows post WWII.
https://www.vox.com/2015/6/23/8832311/war-casualties-600-yea... (Logarithmic scale, does not include the conflicts of the past 20 years)
just because there's no colonial empires fighting each other, doesn't mean there's peace.