What's interesting to me here is that, it seems like a lot of the causes/triggers to WWI/WWII were due to conflicts between nations and/or assassinations. We don't necessarily have anything as big as 2 equal nations fighting, capitals getting invaded etc. So does that mean WWIII will probably never happen given that we don't have any of of these crazy causes/triggers?
Europe has been fighting vicious wars for centuries, climaxing in WW2. What's kept Europe peaceful since WW2 is the realisation that if they go to war again they might destroy everything! WW 2 was enormously destructive. However the US was not destroyed as Europe was by war, so they have maybe not learned these lessons yet.