WARSAW, Poland — A Polish publishing house is defending its decision to publish a book that says some Poles actively profited from Jewish suffering during the Holocaust – a claim that challenges a national belief about Polish actions during World War II.”Golden Harvest,” by Princeton academics Jan Gross and Irena Grudzinska Gross, argues that rural Poles sometimes sought financial gain from Jewish misfortune in a variety of ways, from plundering Jewish mass graves to ferreting out Jews in hiding for rewards. Gross said the starting point of the book is a photograph showing Polish peasants digging up human remains at the Treblinka death camp just after the war in a search for gold or other treasures that Nazi executioners might have overlooked. Scattered in front of the group are skulls and bones. The thesis challenges a widespread view among Poles that their nation, which was occupied by Germany throughout World War II, by and large behaved honorably during that time. Six million Polish citizens – half of them Jews – were killed during the war and memories remain strong of Polish suffering and sacrifice. Heroic Polish deeds – like the Warsaw Uprising of 1944 against Nazi rule – are a foundation of the national identity, while the state in recent years has regularly bestowed honors on Christian Poles who risked their lives to hide Jews from the Nazis.