To a large extent yes. First avgas and then pretty much everything that they were importing from areas outside their control No. The IJN fuel reserve at the start of the war was predicted to last 2 years in peace time or 18 months in war time. It was really only adequate for about a year of wartime operations. Yes. No They weren't by most reasonable measures. Witness the war warnings. NO. It would be interesting to see these ??? They had a non-aggression pact with the USSR why should they consider a German one treason?