LEGENDARY NBC ANCHOR Tom Brokaw had just returned to work on Sept. 11, 2001, after taking the summer off. A friend asked how it was to be back in the saddle. “I’m doing fine but there’s no news,” Brokaw, now 81, complained. “It’s hard to get cranked back up.” Little did anyone know everyone’s world was about to be changed forever. At 8:46 a.m. on that splendid, crisp September morning, a plane…