watching a classic tragedy unfold

From J.D. Salinger's obituary in Friday's Washington Post:

He was unable or unwilling to sustain close personal relations with anyone, she (his daughter) said. "His search…led him increasingly to relations in two dimensions: with his fictional Glass family, or with living 'pen pals' he met in letters, which lasted until meeting in person, when the three-dimensional, flesh-and-blood presence of them would, with the inevitability of watching a classic tragedy unfold, invariably sow the seeds of the relationships undoing."