History /
Poland did reasonably well in land terms out of the postwar settlement [270]
Why would be that? What moral ground possible Germany could have to enter into such dispute?
Listen, what I write now is completely hypothetical, but as you said: We are just writing here. The vast majority of Germans made their peace with the Oder-Neisse-Border and there is no demographical basis in Germany to repopulate lost territories in the East. Our population is shrinking as is the Polish one, too, by the way.
But let's play an intellectual game: The EU collapses and national egoism returns into the European political agenda. Every man for himself, is the new motto! A new nationalistic government in Poland starts to make territorital claims to Lithuania, Belarus, Ukraine and the Czech Republic. Germans get exacerbated about that fact and also vote a nationalistic leader, who reminds them at the glorious past of their nation in the territories East of Odra-Nysa, and then the German-Polish relations deteriote again. Then Germany finds an agreement with Russia and the Polish neighbor states, and then you would have a problem, because the Polish geo-strategical situation hasn't changed at all. Poland is a big, important nation, but Germany and Russia are bigger and more important!
And as far as the mass expulsion of Germans after 1945 is concerned: Morale is not an amplitude in cross-national jurisprudence. You will not find an international law that allows the disappropriation and mass expulsion of 8 millionen German civilians from the German eastern provinces. Therefore if the zeitgeist changes you never know what could be possible.
It would be better just to leave anything how it is, and the more Germany and Poland co-operate the less is the probability that there ever will be a war again between our nations. If you deny the right of Ukraine, Belarus and Luthuania to govern former Polish territories you corrupt the right of Poles to govern your western and northern provinces. Also, Poland would not find any allies in Europe that would support her territorital claims.
They have only themselves to blame for their eastern border.
I won't argue that, as most of my countrymen wouldn't.