When Bill Callahan started releasing albums in his early 20s as Smog, he was like a musical Methusaleh, making songs that were prematurely bitter and world-weary. Now in his 40s, the Silver Spring native is exhibiting a slightly more optimistic perspective and musical growth that are perfectly age-appropriate. After 13 full-length albums, he has put away man-childish things—lo-fi recordings, flashes of misogyny, and the Smog moniker. Sometimes I Wish We Were an Eagle, Callahan’s second project under his own name, is clearly the work of a man who is finally, if tentatively, comfortable with himself. The journey to where he is now hasn’t been the straightest road. Callahan may as well be describing his own shifting temperament on opener “Jim Cain,” when he sings, “I used to be darker/Then I got lighter/Then I got dark again.” Sometimes I Wish We Were an Eagle, with its expansive, string-laden sound and unapologetically country style, is close kin tothewide-open, countrified A River Ain’t Too Much to Love, the first recordCallahan made after moving to Austin, Texas, in 2004. Callahan, over the course of his career, has ventured from lo-fi recordings to straight indie rock to baroque orchestral pop, but country is a perfect fit for him—even though he’s poked fun at the genre and his work within it. On 1992’s Forgotten Foundation, Callahan wrote the tongue-in-cheek “Bad Ideas for Country Songs I and II,” which included such barstool gems as “I need a strong drink on a weeknight/I need a weak girl who won’t put up a fight.” Despite his mixed feelings about country and western, its tradition of heartbreak, black humor, and gritty determination suits the middle-aged Callahan. Fittingly, on “Eid Ma Clack Shaw,” Callahan sings from the perspective of a horse (equine themes are a recurring Callahan motif): “I flipped my forelock/I twitched my withers/I reared and bucked/I could not put my rider aground/All these fine memories are fuckin’ me down.” As the song builds tension through rising horns and strings, Callahan sings the nonsensical, Welsh-sounding title chorus, as if to suggest that words, his tools of trade, are sometimes insufficient. “Invocation of Ratiocination” is an anomaly: It’s an otherworldly instrumental piece that is actually reminiscent of the early bedroom experiments on his debut, 1990’s Sewn to the Sky. Despite that one song, the whole of Sometimes I Wish We Were An Eagle shows how much Callahan has grown as a man and as a songwriter. This is not the pale, bitter depressive who once threatened an ex by singing, “I’m gonna be drunk/So drunk/At your wedding.” Callahan is now, as he sings on the sprightly “Rococco Zephyr,” as “jaunty as a bee.” Callahan, as Dylan might say, was so much older then; he’s younger than that now.