I would assume it was drunken, testosterone-pumped big talk. I would let them babble themselves out, and then talk to my spouse about it later, privately. I would ask him what all that talk was about, and warn him that even talking about that kind of stuff can get you into trouble if someone overhears it and thinks it's an actual plan.
Since just talking can be taken as conspiracy, and conspiracy is a serious offense, I would warn him to keep his joking a little more obvious. If it turned out he was serious, I would tell him that I can't be around for that, and I will do what I need to do to protect myself legally. If we were married, I would tell them that spousal privilege may keep me from relating what he's said, but there is no protection if I actually witness actions, and I'm willing to report those.
Then I would get myself safely away.
I would try to stop them and would tell them they should not do anything bad. But if they really would do and I'm being called as a witness then I would tell only what I have heard.
If that happened then I would probably wonder what the heck I was doing with this person who obviously didn't share my believes. I may not run to the police because even the police will want some proof rather than drunken rambling. On the other hand, I might just tell the police and then find myself a good divorce lawyer if I were married or suddenly find myself single if not married to the person.
Anyone who could conceive of doing this in a drunken state would probably not have issues with it in a sober state as well. This means my very life could be at stake should I do something that might bring out a similar reaction. So, I would try to extricate myself from the situation and the relationship as soon as possible.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.