Did I lose that fort in a tie, or a natural 7?

I've been re-reading the rules of Struggle of Empires, and just came across the following which I hadn't fully absorbed before, relating to combat:

"...In the case of a tie both sides lose a unit but the defender does not lose a control token. A fort is never lost in a tie, no matter what the circumstances are..."

Now, I remember in the last turn of our game the other night, Craig attacked my one token in the German States. The result was that my control token stayed in place, but I lost my defending fort. I can't remember now whether this was because of a tie or a natural 7. But if the former, the outcome of the game could have been quite different because of a misunderstanding (ie; forgetting) of this rule.
A tie should have meant that I retained my fort. In this case perhaps Alex would have been deterred from attacking here, and instead chosen a different and less lucrative target. Or even better, he might still have attacked but actually lost - my Army Training would have been in effect to give me +3 on the original roll, not counting allied support from Pat. As a result, I might not have had to spend my last turn attempting to gain back this token, and instead would have been able to win domination in the East Indies as planned...

Yes, this is all history now, and falls into the "if only I'd...", and "could've, should've, would've..." files.
Arguably I should be doing something more useful with my time than re-hashing past battles and game rule details. Clearly I've still got SoE on the mind. You know, it'd be good to play this again some time soon! :-)