[Ironhawk]

In my opionion NAPs are actually composed of two parts, one explicit, the other implicit:

Part 1) Rules: The actual rules of the NAP, which both players agree on. The default NAP stating only that players may not militarily attack each other.

Part 2) Courtesy: The process of staying away from (or informing before taking) actions which will irritate your NAP-partner. Taking globals, stealth preaching, supporting thier enemies, etc...

Of course if someone violates the rules of the NAP it is immediately terminated. But the situation is far more murky if the NAP-partner is just being discourteous and must be handled on a case-by-case basis. If I do feel that if a NAP-partner abuses the common courtesies in a seriously bad way that screws up my plans (or if I detect a pattern of interference on thier part) that I will void the NAP.