Greenpeace is both halves of the name.
While I agree that nuclear is green, IMO Greenpeace are correct about it not being compatible with the "peace" half: the stuff that makes working reactors is the most difficult part of making a working weapons.
This also means that during the cold war they suspected of being soviet plants.
Those suspicions and yours could both be correct for all I know.
Also nuclear requires a powerful state to manage it safely, which has peace-related side effects.
There's a fun game you can play with countries that build nuclear power plants: "guess the existential threat".
In each case it's pretty obvious. Either they have nuclear weapons that share a supply chain and skills base or there is an existential threat out there.
In Poland's case you can tell when they started seeing an existential threat from when they suddenly got interested in building a plant.
I've heard and think I've read multiple times that Greenpeace was fueled by Soviet monies to prevent Western energy independence and economic takeoff.
I don't have sources and would appreciate if anyone has anything to offer on this.
> the stuff that makes working reactors is the most difficult part of making a working weapons
I'm unaware of this to be true. Civilian reactors are hardly-at-all-enirched uranium reactors. Creating highly enriched uranium or plutonium are completely different processes.