> So any nation state needs to be energy independent?

It is obviously a good thing if a democratic nation state is independent from a totalitarian dictatorship.

> Not like life expectancy in Germany is low, for example.

It's not about life expectancy. They now have to make a choice between supporting an aggressive totalitarian state vs. suffering damage to their economy due to higher energy prices. That is obviously a bad position to be in.

Why is using domestic energy sources much more not another choice now or in the recent past?