True. Still, from what I know, he saw himself as a patriot. Which was the reason why he opposed the Nazis but the reason why he didn't defect or betray the Germans.
If by "the Germans" you mean the German government, he did betray them, at least when it to war crimes and the Holocaust. I don't know if he also sabotaged the war but that would also be consistent with patriotism. A patriot loves his country, that doesn't mean they don't care about others at all. That would be some sort of combination of patriotism and psychopathy.
A patriot could also have decide d to sabotage the war effort to end the war faster, to get rid of Hitler or to somewhat save the reputation of Germany.
He didn't openly defect but that doesn't mean much for a spy.
From what I remember of the documentation I saw about him back the day he never actively sabotaged the war effort or did things that sis put German troops in danger. He opposed the Nazi regime.
Yes, I agree it is quite a feat of mental acrobatics. My impression was that he somehow seperated Nazis and the German nation. And that the war was a German and not really a Nazi thing. Maybe he just didn't want to see that Germany and the Nazis were the same thing at the time, maybe he also wanted a round two after WW1 or maybe he wasn't able to shake decades of upbringing and training.
Either way, he was one of the few "good" Germans, even if not on Schindler levels, and definitely a very interesting person. Just look up his WW1 adventures.
Notable, so, is that even in WW1 and after he was not necessarily a trained spy intel guy, AFAIK.
I didn't read much about Canaris but I don't think his stance required much mental acrobatics. Considering a nation and its government somewhat separate entities is quite normal.[1] Of course many Germans used this as an excuse after the war but this does not apply to Canaris.
Considering wars of aggression acceptable wasn't all that unusual either.
Sabotaging the war effort would have meant helping the Allies fight Germany. Sabotaging war crimes and the Holocaust meant trying to stop Germany from something evil and stupid (at least if he considered German Jews German). While there were reasons for a patriot to sabotage the war effort, only sabotaging the crimes was also a consistent position.
[1] Especially when it isn't democratically elected. The last multi-party elections in 1933 weren't free. The communist Reichstag members were jailed, many others were intimidated to make them support the enabling act.
Summing it up pretty well. And yes, that is how I understood Canaris. And yes, from his perspective it seems a logical stance to take. Hindsight makes a lot of things easier, doesn't it? Also true that he saw what the Nazis really were and did something about itt. A rare feat during these days.
https://en.wikipedia.org/wiki/Wilhelm_Canaris