[thejeff]

I think this discussion may point at a fundamental disagreement. Some view only direct attacks (or indirect damage from globals) as breaking a NAP, others view some globals that put the caster in a dominant position as sufficient.
Essentially, this doesn't hurt me directly, but if you're not stopped quickly you're going to win, which doesn't just hurt me, it destroys me.

Similarly, would a sudden attack which leaves the NAP partner on the brink of winning via Victory Conditions justify breaking a NAP? Say siegeing enough VP castles to win on the next turn.

I'd be happier living with some globals that do hurt me directly than with some of the power boosting ones. The random lightning strike one should count, but I'd rather live 3 turns under that than wait 3 turns while a someone has the Forge or Arcane Nexus up.