Good morning from Washington, where the idea of widespread voting by mail in November is a dividing line for liberals and conservatives. What’s going on in Nevada should worry Americans, the state’s former attorney general writes. Plus: Barack Obama’s about-face on the wisdom of the filibuster; 75 years since Hiroshima and Nagasaki; and what’s happened to our families. On this date in 1974, President Richard M. Nixon, facing a House impeachment vote, goes on television to announce that he will resign the next day. Enjoy your weekend.