Cooperation against disasters. part1

Hi!
That's my first record in English. I studied it so long, but result is so poor )) But I want to share some thinks...
Today we live in the time when many problems separating peoples in the past are disappeared. There are not ideological disagreements now, like in the cold war time. I think XX century must be the last century, when war was considered like an political instrument. Today war absolutely unacceptable as solution of political problems between countries.
I think politicians understand this situation well, but they can't to change "old cold war thinking" immediately. Really, today I don't see any "clash of interests" between Russia and US, or Russia and Europe.. or other countries that required to maintain an army like in the past cold war time.
Clash of the economical interests today can't be solved using military forces! So, the lagre armies in many countries are just a rudiment of cold war.
I think 2000 year is symbolic line separated old "age of barbarism" and new "age of civilisation". 20 th century was really the top of "barbarian age" when dosen of millions people was killed...
(Tell me, please, why they was killed, for what high purposes? )