I used to believe that. Started to doubt during my stint in the Army. Read Daniel Ellsberg's memoir and realised. Its not rational to believe they will behave rationally as a group and a system.

There are no JFKs in the world today. There are no Khrushchev's either. There are a bunch of unprincipled, entitled midwits playing chicken on a railway line as they try to pick each other's pockets.

Ellsbergs book: