Here & Now’s Jeremy Hobson looks back at some of the political and social issues of the year with A. C. Wharton, who was mayor of Memphis, Tennessee, from 2009 to 2015. Also, we put some of 2018’s biggest science stories — gene-edited babies born in China, a new probe landing on Mars and the death of acclaimed physicist Stephen Hawking — under the microscope. That and more, in hour one of Here & Now’s Dec. 25, 2018 full broadcast.