Yeah, I heard about using your own threat in this regard, but I could never figure out how that works.
Thank you for this contribution, Iwo Jima.
With my pleasure
When you will conquer Hungary, you will get high threat on most neighbours. So, you could use your own threats on them instead of their threats.
This called in game "mutual threat", so, you can DoW a country that threats you, or instead the country, that could DoW you, because you threat them. (preemptive strike)
There are also some modificators for Axis (-25%) and in a case you have your cores in target country (-20%). e.g., Germany to DoW Poland has -45% Modifier. If Romania cede Bessarabia to USSR, dowing USSR will be more easy ))) Hope, you will not do this)))