The title of Ray Yamanouchi’s new play suggests there is only one American tradition. Is it fireworks on the Fourth of July? Is it celebrating Thanksgiving? Or is it putting out flags on Memorial Day? The walls at the 13th Street Theater hint that Yamanouchi’s view is much darker. There are posters for shows like A Darkey Misunderstanding and the musical Big Minstrel Jubilee by William H. West (1853–1902) and one that cautions “Negroes Beware: Do Not Attend Communist Meetings,” along with a 19th-century advertisement about the Democratic Party (the face of a white-bearded man) and the Republican party (a black man with unruly hair). More modern flyers hang there too: a picture of Angela Davis with the words “Black Power” and a recent Black Lives Matter poster.