I honestly believe that if I had the ability to release my puppet, the Soviet Union never would have attacked me.
I decided early on to go through Scandinavia and I puppeted Finland which turned out to be a huge mistake when I realised the Soviet Union had either used a focus or justified on them, now I thought 'no sweat I'll just release Finland somehow, and I'll go back for it later after the USA is done', nope, apparently you can't do that and I ended up in a war with the Soviet Union who just bulldozed through me. So I'm playing Nazi Germany for the New World Order achievement and I'm in the middle of an invasion with the USA that requires the majority of my troops to fight.