Optimism is good, but it could have turned for the worse: we are lucky that we had the 'nuclear taboo' ; nukes are kept strictly as a weapon of last resort. If nukes were to be used in 'limited conflicts' then we all would life in quite shitty place. (in the real world nukes kept Europe safe and prevented big wars between regional/superpowers)

I think we should be thankful for our extreme luck.

You never know how the next advance in science & technology will change the pace and character of human conflict.