[kubanczyk]

The elephant in the room is nuclear weapons. Take a hard look when the history actually changed.

As long as politicians didn't fear for their own precious lives, they didn't mind throwing heaps of others' lives to shift the balance of power by 1%. They weren't starting these wars for merely economical value of land or money - it was always about (non-economical) value of power. Since 1945-1949, the stakes are suddenly too high and that's why don't have major wars anymore.

[aeternum]

Nuclear weapons is significant, but recently I've been considering how much information also plays a part.

Information about other powers is much more accessible now and spying is easier given the internet. If they weaker power knew beforehand that they were in fact weaker, it makes no sense to challenge.