The last thing you want is for Germany to rise back up again. They’re already openly antagonistic towards the USA, even going so far as to call the USA their enemy of late; give them a European Union military and they will use it in an offensive rather than defensive manner.
As I understand things, the calls to “step up” have to do with the framework of the USA continuing to be the great power; not them instead of us.
And that's what German haters fear the most !