NATO is realpolitik. It might be that you don't know its origins, what it represents and what its mechanisms are. I recommend you study it. And by the way: It goes both ways. The defence pact is reciprocal. When the US is attacked, all members of NATO are obliged to contribute for its defense and offense as well. It is not a one way thing where the US only contributes one direction.

It is most certainly NOT braindead. You Sir, are wrong.