I was born in 1951 and have faint recollections of the Hungarian uprising and Suez in '56. The 1970s saw troubles in N. Ireland, the middle east, the Vietnam war. I can also remember the French fighting in Africa before giving up their colonies, Apartheid , Powell and Paisley stirring up hatred, the Falklands crisis and the advent of AIDS.
Somehow, we just got on with living through it all, didn't we?
Your grandchildren will too, through whatever they have to tackle.
It's understandable you are concerned for them, but if you look at my list I am sure you can fill in all the good things that happened, which I have left out.