The May 1926 coup d’état in Poland inaugurated what has become known as the period of sanacja or “cleansing.” The event has been explored in terms of the impact that it had on state structures and political styles. But for both supporters and opponents of the post-May regime, the sanacja was a catalyst for debate about Polish national identity, about citizenship and responsibility to the nation, and about postwar sexual morality and modern gender identities. The Clash of Moral Nations is a...