A Maryland man who sent dozens of threatening letters to Jewish institutions across the country — including the Weitzman National Museum of American Jewish History in Center City — was sentenced Monday to more than three years in federal prison. Clift A. Seferlis, 55, of Kensington, Md., apologized for his actions during a sentencing hearing in Philadelphia’s federal courthouse, saying he’d written the letters because he’d become consumed by a sense of moral outrage over the suffering of Palestinians amid the war in Gaza. He said he never intended to act on his threats and was not a violent person,...