i am a naturalized american who used to have a different passport most of the life. I've pondered who I would support in a hypothetical war between the countries. I haven't been able to resolve this.
The one who's less guilty of humanitarian violations in that scenario? Don't support America, Russia, or China when they act to make peoples' lives worse. It's like having two really good friends (husband and wife) and the husband starts beating the wife. You're not going to support him just because he's the closer friend. With that said, it's important to remember that many people will do just this and immigrants in a country can wrongly support their origin country. cough supporting Russia right now cough
I would hope it is to the country you chose to pledge an Oath of Allegiance to in order to obtain the new citizenship and all of the benefits it has granted
That (circumstances) was not entered into the equation, so I took it to mean all things being equal. Otherwise how could one possibly ponder which side until those circumstances are known, there was no hint that circumstances where being considered