The Soviet Union was definitely an existential threat - not just to the US but to any country with liberal values.
Germany attacked its largest trading partner, France. More than once. People do not always act rationally or in their best interests. This is why deterrence is important. Rational people don't want to fight wars.
The recent forever wars are driven by neocon thinking. Neocons are statists (people who believe the state has the best interests of the people and are the best solvers of problems) who extend domestic agenda to international agenda. Hence, Iraq limited war (Bush I) gets turned into a project to rebuild Iraq into a western liberal democracy (Bush II). Afghanistan grows from a successful special operation to a futile state rebuilding exercise.
When you're the only super power, the way adversaries beat you is by getting you to punch yourself in the face by over reacting, acting out of pride, or giving in to fear.
To be fair, in WW2 Germany did not attack France - it attacked Poland, and expected that France would not keep its alliance and give it up just as they folded on Sudatenland and the rest of Czechoslovakia, but France did attack Germany over that; and arguably if the German expectations about French/British reaction turned out to be true, then annexing Poland would be in their best interest according to what was beneficial for states in early 20th century (now the economic incentives have substantially changed).
"[..] gets turned into a project to rebuild Iraq into a western liberal democracy [..]"
It's like the third time in a week that I read this nonsense somewhere.
Obviously,Iraq was not invaded "to bring democracy".
Also there is the assumption that the people that make this decisions care at all about democracy, you get to kill half a million people and still be the good guys:
"See? we bombed them because we wanted to bring democracy, too bad they were not ready for it. Maybe it was a mistake but done with the best of intentions!"
Germany attacked its largest trading partner, France. More than once. People do not always act rationally or in their best interests. This is why deterrence is important. Rational people don't want to fight wars.
The recent forever wars are driven by neocon thinking. Neocons are statists (people who believe the state has the best interests of the people and are the best solvers of problems) who extend domestic agenda to international agenda. Hence, Iraq limited war (Bush I) gets turned into a project to rebuild Iraq into a western liberal democracy (Bush II). Afghanistan grows from a successful special operation to a futile state rebuilding exercise.
When you're the only super power, the way adversaries beat you is by getting you to punch yourself in the face by over reacting, acting out of pride, or giving in to fear.