That's the only valid point you've made.
But what if Turkey were to attack its NATO ally? Let's say, to defend the "Macedonian minority of Greece"?
Where would the US stand, and how far would the US be willing to take it, with either ally?
Thing is, the US is trying to stop Russian influence in the area, but it's doing it in such an idiotic manner, that it really is achieving the opposite.
Overexpanding the alliance, particularly by bringing in a country that is most likely going to have huge internal issues in the near future because it has a minority numbering almost 1/4 of its population, and has caused armed conflict in the past, is just asking for it. Particularly given that the "parent" country of this minority is already in NATO, and is an very close ally of the number one country in NATO that is questioning US domination of the alliance (with the support of Russia itself).
But all that seems to be too complicated for US policy makers. Oh, well.