Say there is a non-NATO, non-EU country, yet not Ukraine, at least not yet. (I stipulate the last because I don't want the current crisis to yet color the answers.)
What are the actual requirements for defense and/or aide, if:
The country is granted EU, but not NATO membership?
The country is granted NATO, but not EU membership?
Do things drastically, or at all, change if both are granted?
Yes, there are multiple questions here, and if the answer would truly be unwieldy to answer both main questions, then I would accept closure. What I am looking for are what are the other EU countries required to do to aide or defend an EU nation from attack by a non-EU nation? Conversely, what are other NATO countries required to do if the same happens? I'm hoping it is possible to bullet a list, or something.