Chris Willman Senior Music Writer and Chief Music Critic It’s been a challenging time lately for Maren Morris in the country music world, as her views on key issues of the day have been in conflict with those of some of country’s more right-leaning artists or fans. She addresses the toll this has taken on her in a music video that came out Friday morning for a new song, “The Tree,” that makes it clear she’s feeling some estrangement from the genre, or even ready to think about moving on — although, ironically, the style of the song couldn’t be more country.