Open this photo in gallery: Polish soldiers and a local dog walk along the border fence on the Polish-Belarusian border in Usnarz Gorny, Poland, on Aug. 30.KUBA STEZYCKI/Reuters “Only pigs sit in the cinema.” That phrase was coined during the Second World War by the Polish Home Army to discourage people from seeing Nazi propaganda films screening in German-occupied Poland. But the resistance slogan is getting new life in today’s politically charged Poland, as controversy swirls over the feature film The Green Border, which has caused the far-right Law and Justice (PiS) government to lash out and compare the movie...