Good questions!
Here’s another:
Both are part of the NATO Alliance. According to the NATO Charter, an attack on one is an attack on all.
So... If they come to blows...
Do we fight BOTH of them?
Ha! I used to wonder about this when I was a US troop under NATO and stationed in Europe and tensions between Greece and Turkey would flare up.
The only answer I could come up with then was, yes, fight both of them until they back down.