Yes Poland was not formally at war with USSR, but USSR never the less invaded Poland in 1939 without a declaration of war. I would however not hesitate to call it war. USSR captured some 200 000 Polish resistance back the. I was not really debating the Kresy issue. It's of course a sensitive subject but there is a lot of German towns and cities in the western part of what is today called Poland. Poland have also been independent, again, for a few decades. So theoretically Poland could have returned what was forced upon them, but have not really felt the need for it
Regards, Lars
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