At 89, Philip Glass pulls no punches. “After thoughtful consideration,” he wrote in January, “I have decided to withdraw my Symphony No. 15 ‘Lincoln’ from the John F. Kennedy Center for the Performing Arts. Symphony No. 15 is a portrait of Abraham Lincoln, and the values of the Kennedy Center today are in direct conflict with the message of the Symphony. Therefore, I feel an obligation to withdraw this Symphony premiere from the Kennedy Center under its current leadership.” In March, the other shoe dropped. Rather than Gianandrea Noseda leading the National Symphony Orchestra, the noted Glass specialist Karen Kamensek would lead the Boston Symphony Orchestra in the premiere at Tanglewood, the ensemble’s bucolic summer residence. (That Kamensek is a new face to the Boston musicians is unremarkable; that they have never before played a note of Glass is shocking.) The baritone Zachary James—Hades in the 2024 London premiere of Hadestown—will be heard in Lincoln’s early “Address Before the Young Men’s Lyceum of Springfield, Illinois” (1838) and other texts of America’s 16th president, concluding with his farewell address. On paper, this looks like the gesture with which a well-built program would conclude, but at Tanglewood, it brings us to intermission. The celebration of the Great Emancipator then continues with excerpts from the John Williams soundtrack for the Steven Spielberg biopic plus that old standby of Aaron Copland’s. —Matthew Gurewitsch