Well, to some extent one might argue than nations rarely change.
That's something I'm wondering about.
Characters might not change but the conduct of nations under different leaders can change a lot.
The views and behaviour of Germans and the conduct of Germany as a state clearly changed a lot from that of Nazi Germany. The views, behaviour and mentality of RuSSians and the conduct of RuSSia as a state practically didn't change at all.
One way or another, I refuse to accept that Poland and Russia are doomed for eternal enmity.
I am not all-knowing God and I don't know what will happen in distant future and if RuSSian nation can change or not. I just see what I see and I draw conclusions from both history and the present day reality.
Poland will be able to get along with RuSSia only if RuSSians will change for the better. There's an option that Poland will change for worse and then it will get along with the authoritarian, f*cked up RuSSia, but I wouldn't like to live to such times.