War and future

I come from beautiful country which was devastated by war. War in Bosnia lasted for 4 long year in period since 1992 to 1995. I don't remember the war cause i was born just few after the war started. But my father,mother, and many other people still can't forget the horror they witnessed. I can only see building ruined and many graves of our heroes.20 years after people in Bosnia are under great influence of what happened during those years. I hear stories everyday about wars raging in Africa and middle east. What's the point of war? My father was a soldier and I know he would do anything to save me from that experience.
America has history no more than 300 years old and they've been in more wars than half of the Europe. Why did USA attacked Vietnam or Korea? 200 countries work on peace, only they attack everybody and everything. I don't get it. In last couple of week situation between Russia and Ukraine is very intense and USA just made the situation worse. These countries hate each other for decades, this kind of communication can only bring more problems. If they have unresolved issues they should do something about it in privacy. There is no need to alert whole world because Putin hates Obama or other way around. 95% of you didn't taste war or what's coming after the war. I did so I know, nobody needs or deserves that. Many of my friends lost their parents,brothers,sisters during the war. Most of war victims are civilians so wars should be ended an killing must stop.