The reason why I'm being careful to present my reasoning is because I hold with the general philosophy that being a trustworthy actor will net me more advantage in the game over the long run than being an untrustworthy one.
Breaking an agreement to gain an advantage in one game is likely to cost me even more in other games if people won't trust me diplomatically.
So if I've made a mistake here, it was an honest one. I guess I attributed more ferocity to Ragnar's Wolves than was warranted.
What you say about the strategic position is true; I probably would have formally terminated my NAP with Abysia sometime soon in the proper manner. Thinking I was soon to be attacked caused me to rush my timetable and preparations, however.