U.N. Secretary General Ban Ki-moon, who for six years stonewalled Haitians’ claims that poor sanitation practices of U.N.-supervised troops stationed in Haiti after the devastating 2010 earthquake caused a cholera epidemic that has left 10,000 dead and 800,000 infected, now admits responsibility. But not total responsibility—as an official statement released Aug. 19 suggests. Veteran journalist and documentarian Kim Ives, editor …